Novel compounds for the management of aging-related and diabetic vascular complications, process for their preparation and therapeutic uses thereof

ABSTRACT

Novel compounds of the pyridinium series useful for the management of diabetes and aging-related vascular and neurovascular complications, including kidney disease, nerve damage, atherosclerosis, retinopathy, inflammatory disorders, immunological disorders, oxidative stress, dermatological disorders and discoloration of teeth, by breaking preformed AGE, of the general formula I, or pharmaceutically acceptable salts thereof,  
                 
 
     wherein, R 1 , R 2 , R 3 , X and m are as defined in the specification. Also disclosed is a method for preparation of the compounds of general formula (I) and pharmaceutical composition containing one or more compounds as defined above as active ingredients. Also disclosed is a method of treatment of a diabetic patient by administering the compounds as defined above, either singly or in combination with drugs for antidiabetic therapy.

[0001] This is a continuation-in-part application of application Ser. No. 09/801,778 filed Mar. 09, 2001 which is a continuation in-part application of application Ser. No. 09/598,410 filed Jun. 21, 2000, which is a continuation-in-part application of International Application No. PCT/IB99/01683 filed on Oct. 15, 1999, the disclosures of which are incorporated herein by reference, which International Application has been published by the International Bureau in English on Apr. 12, 2001.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a new class of compounds of pyridinium series and to their use in treatment of diabetes and related illnesses. More particularly the invention relates to compounds of this series, methods for their preparation, pharmaceutical composition containing these compounds and their use in the treatment of complications of diabetes mellitus. The compounds of this series exhibit AGE breaking and inhibiting activity, which is essential for the treatment of diabetic and aging-related vascular and neurovascular complications including kidney disease, nerve damage, atherosclerosis, retinopathy, inflammatory disorders, immunological disorders, oxidative stress and dermatological conditions. The invention also extends to the method of reversing the discoloration of teeth resulting from nonenzymatic browning in the oral cavity which comprises administration of an amount effective to reverse pre-formed advanced glycosylation crosslinks.

[0004] 2. Description of the Related Art.

[0005] Maillard in 1912 found that reducing sugars, such as glucose and ribose react with proteins to form brown pigments. Further studies have shown that this is an irreversible non-enzymatic reaction, which occurs in several natural systems including stored foodstuff. Maillard reaction occurs in two stages, early and advanced. Initially, proteins react with glucose to form stable Amadori products, which subsequently cross-links to form advanced glycation end products (AGE). In most cases, the formation of AGE also accompanies browning of the proteins and increase in the fluorescence.

[0006] In diabetes, where blood glucose level is significantly higher than normal, the reaction of glucose with several proteins such as haemoglobin, lens crystallin and collagen, gives rise to the formation of AGE, which in turn, is responsible for the complications associated with diabetes, such as nephropathy, microangiopathy, endothelial dysfunction and other organ dysfunctions. In addition, the activity of several growth factors, such as basic fibroblast growth factor, is also impaired. AGE products, unlike normal proteins in tissue, have a slower rate of turnover and replenishment. It has been reported that AGE products may in fact elicit a complex immunological reaction involving RAGE (Receptor for Advanced Glycation End Products) receptors and activation of several incompletely defined immunological processes. It has been documented that diabetes with evidence of microangiopathy and macroangiopathy also show evidence of oxidative stress, the mechanism of which has not been elucidated.

[0007] In vitro AGE formation can be studied in the laboratory by incubating reducing sugars, such as ribose or glucose with bovine serum albumin. AGE formation can be detected by increase in the fluorescence or increased cross reactivity with anti-AGE antibodies. The increase in fluorescence seems to precede formation of AGE specific antigenic epitopes. This increase in fluorescence is used to monitor the increased AGE formation in vitro (Brownlee M et al, Science 1986; 232:1629-1632). In addition to the increase in the fluorescence, one of the most important features of in vitro AGE formation is the formation of antigenic epitopes that are specific to AGE and not to the native proteins. Therefore, it is possible to raise antibodies against advanced glycation end products of one protein and use them to detect AGE formation in other proteins. This has served as an important analytical tool in AGE research.

[0008] Due to the clinical significance of AGE formation, many approaches are being used to diagnose, prevent, or revert AGE formation in the body. The formation of AGE could be inhibited by reacting with an early glycosylation product that results from the original reaction between the target protein and glucose. The inhibition was believed to take place as the reaction between the inhibitor and the early glycosylation product appeared to interrupt the subsequent reaction of the glycosylated protein with additional protein material to form the cross linked late stage product. Compounds like aminoguanidine act to inhibit AGE formation by such mechanism.

[0009] The formation of AGE on long-lived proteins is also associated with cross-linking of these proteins. The AGE derived protein cross-links have been shown to be cleaved by compounds like N-phenacyl thiazolium bromide (PTB), which reacts with and cleaves covalent, AGE derived protein cross links (Vasan et al. Nature 1996; 382: 275-278; U.S. Pat. No. 5,853,703, Date of Patent: Dec. 29, 1998). The mechanism of reducing the AGE content in tissues is expected to take place relatively rapidly, in contrast to aminoguanidine, which acts slowly by its very nature of mechanism of action. This current specification is related to compounds of pyridinium class, which break pre-formed AGE, like PTB, and in some cases even more effectively by than PTB.

SUMMARY OF THE INVENTION

[0010] The main objective of the present invention is to provide a new class of compounds of the pyridinium series which are useful for the management of diabetes and aging related vascular and neurovascular complications and particularly in the treatment of complications of diabetes mellitus and other aging related conditions including kidney disease, nerve damage, atherosclerosis, retinopathy, inflammatory disorders, immunological discorders, oxidative stress and dermatological conditions. The invention also extends the method to reverse the discoloration of teeth resulting from nonenzymatic browning in the oral cavity which comprises administration of an amount effective to reverse the pre-formed advanced glycosylation crosslinks, etc.

[0011] Another object of the present invention is to provide compounds of the pyridinium series, which exhibit AGE breaking activities.

[0012] Yet another object of the present invention is to provide a method of preparation of compounds of the pyridinium series which exhibit AGE breaking activities.

[0013] Still another object of the invention is to provide pharmaceutical compositions with a new class of compounds of the pyridinium series according to the invention and their pharmaceutically acceptable salts in combination with suitable carriers, solvents, excepients, diluents and other media normally employed in preparing such compositions.

[0014] Still another object of the invention is to provide a method of treatment of a diabetic patient by administration of the compounds of the invention, either singly or in combination with drugs for anti-diabetic therapy, or pharmaceutically acceptable salts thereof in required dosage in admixture with pharmaceutically acceptable diluent, solvent, excepients, carriers or other media as may be appropriate for the purpose.

DETAILED DESCRIPTION OF THE INVENTION

[0015] The present invention provides for a new class of AGE breakers, of general formula I,

[0016] wherein

[0017] R₁ is —R₄—R₅ or —N(R₇)N(R₇)R₉;

[0018] R₄ is selected from the group consisting of —N(R₇)R₆O—, —N(R₇)R₆N(R₇)—, OR₆O, and —OR₆N(R₇)—, where R₆ is alkyl with C₂ to C₈ carbon atoms;

[0019] R₅ is selected from the group consisting of alkyl, aryl including heteroaryl, —COR₇, SO₂R₇, —C(S) NHR₇, —C(NH)NHR₇, —COR₁₀,

[0020]  where R₇ is selected from the group consisting of H, alkyl and aryl including heteroaryl provided R₇ may be the same or different for R₁ and R₃ in the same compound;

[0021] R₂ is selected from the group consisting of F, Cl, Br, I, OR₇, NO₂, alkyl, aryl including heteroaryl, formyl, acyl, C(O)NR₇R₁₀, C(O)OR₇, NR₇R₁₀, N═C(R₇)(R₁₀), SR₇, SO₂NH₂, SO₂ alkyl and SO₂aryl, and m is 0, 1 or 2;

[0022] R₃is selected from the group consisting of R₇, OR₇, N(R₇) (R₁₀), N═C(R₇) (R₁₀), N(R₇) N(R₇) (R₁₀), N(R₇) N═C(R₇) (R₁₀) and CH(R₇)C(O)R₈ where R₈ is selected from the group consisting of R₇, OR₇ and NR₇R₁₀;

[0023] R₉ is selected from the group consisting of hydrogen, alkyl, aryl including heteroaryl, C(O)R₁₀, —SO₂R₁₀, —C(S)NHR₁₀, —C(NH) NH (R₁₀) and —C(O) NHR₁₀,

[0024] R₁₀ is selected for the group consisting of H, alkyl or aryl including heteroaryl and in each case may be the same or different from substituent R₇, provided R₁₀ may be the same or different for R₁ and R₃ in the same compound;

[0025] X is selected from group consisting of a halide ion, acetate ion, perchlorate ion, sulfonate ion, oxalate ion, citrate ion, tosylate ion, maleate ion, mesylate ion, carbonate ion, sulfite ion, phosphoric hydrogen ion, phosphonate ion, phosphate ion, BF₄ ⁻ and PF₆ ⁻; with proviso that,

[0026] (i) when two alkyl groups are present on the same carbon or nitrogen, they may be linked together to form a cyclic structure and

[0027] (ii) the nitrogen of heteroaryl ring of R₁₀, when present, may be quaternized.

[0028] In a preferred embodiment, (iii) R₃ is OR₇ and R₁ is —NHNH₂ then R₇ is not alkyl, and (iv) when R₃ is OR₇, R₁ is N(R₇)(NR₇)R₉ and R₉ is C(O)R₁₀ where R₁₀ is alkyl, then R₇ is not hydrogen.

[0029] As used herein, “alkyl” refers to an optionally substituted hydrocarbon group joined by single carbon-carbon bonds and having 1 to 8 carbon atoms joined together. The alkyl hydrocarbon group may be linear, branched or cyclic, saturated or unsaturated. The substituents are selected from F, Cl, Br, I, N, S, O and aryl. Preferably, no more than three substituents are present.

[0030] As used herein “aryl” refers to an optionally substituted aromatic group with at least one ring having a conjugated pi-electron system, containing up to two conjugated or fused ring systems. Aryl includes carbocyclic aryl, heterocyclic aryl and biaryl groups, all of which may be optionally substituted. The substituents are selected from F, Cl, Br, I, N, O, S and straight chain or branched C₁-C₆ hydrocarbon. The substituents for the aryl group are preferably selected from F, Cl, Br, I, N, O and straight chain or branched C₁-C₆ hydrocarbon.

[0031] The novel compounds of the invention of general formula I having m as 0 or 1 and —COR₁ at position 3 are listed in Table 1A and the novel compounds of the invention of general formula I having m as 0 and —COR₁ at position 4 are listed in Table 1B. The following compounds suggested are by way of example alone of the representative compounds of the general formula I as defined above and in no way restrict the invention:

[0032] N,N′-bis[3-carbonyl-1-(2-phenyl-2-oxoethyl)-pyridinium] hydrazine dibromide (compound 1);

[0033] N,N′-bis[3-carbonyl-1-(2-ethoxy-2-oxoethyl)pyridinium]hydrazine dibromide (compound 2);

[0034] N,N′-bis[3-carbonyl-1-(2-(2′,4′-dichlorophenyl)-2-oxoethyl)pyridinium]hydrazine dibromide (compound 3);

[0035] 1-(2-ethoxy-2-oxoethyl)-3-(2-(2-pyridyl) hydrazinocarbonyl) pyridinium bromide (compound 4);

[0036] 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonylhydrazinocarbonyl) pyridinium bromide (compound 5);

[0037] N,N′-bis[3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl)pyridinium]hydrazine dibromide (compound 6);

[0038] 1-(2-ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethylaminocarbonyl) pyridinium bromide (compound 7);

[0039] 1-(2-(2′,4′-dichlorophenyl)-2-oxoethyl)-3-(2-(benzoyloxy) ethylamino-carbonyl) pyridinium bromide (compound 8);

[0040] 1-(2-thien-2′-yl-2-oxoethyl)-3-(2-(2-pyridyl)hydrazinocarbonyl) pyridinium bromide (compound 9);

[0041] 1-(2-phenyl-2-oxoethyl)-3-(2-(2-pyridyl)hydrazinocarbonyl) pyridinium bromide (compound 10);

[0042] 1-(2-phenyl-2-oxoethyl)-3-(hydrazinocarbonyl)pyridinium bromide (compound 11);

[0043] 1-(2-phenyl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide (compound 12);

[0044] 1-(2-ethoxy-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide (compound 13);

[0045] 1-(2-phenyl-2-oxoethyl)-3-(phenylsulfonylhydrazino carbonyl) pyridinium bromide (compound 14);

[0046] 1-(2-phenyl-2-oxoethyl)-2-chloro-3-(phenylsulfonylhydrazino carbonyl) pyridinium bromide (compound 15);

[0047] 1-(2-phenyl-2-oxoethyl)-3-(2-(acetoxy)ethyloxy carbonyl) pyridinium bromide (compound 16);

[0048] 1-(2-ethoxy-2-oxoethyl)-3-(2-(benzoyloxy)ethyloxy carbonyl) pyridinium bromide (compound 17);

[0049] 1-(2-thien-2′-yl-2-oxoethyl)-4-(2-(benzoyloxy)ethylaminocarbonyl) pyridinium bromide (compound 18);

[0050] 1-(2-ethoxy-2-oxoethyl)-4-(phenylsulfonyl hydrazino carbonyl) pyridinium bromide (compound 19);

[0051] 1-(2-phenylamino-2-oxoethyl)-4-(phenylsulfonyl hydrazino carbonyl) pyridinium chloride (compound 20);

[0052] 1-(2-ethoxy-2-oxoethyl)-3-(phenylsulfonyl hydrazino carbonyl) pyridinium bromide (compound 21);

[0053] 1-(2-(2′,4′-dichlorophenyl)-2-oxoethyl)-3-(2(methoxy)ethyloxycarbonyl) pyridinium bromide (Compound 22);

[0054] 1-(2-phenylamino-2-oxoethyl)-3-((benzoyloxy)ethylaminocarbonyl) pyridinium chloride (compound 23);

[0055] 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenylaminocarbonyl hydrazinocarbonyl)pyridinium bromide (compound 24);

[0056] 1-(2-phenyl-2-oxoethyl)-3-(2-(acetoxy)ethylaminocarbonyl) pyridinium bromide (compound 25);

[0057] 1-(2-phenylamino-2-oxoethyl)-3-(phenyl sulfonyl hydrazino carbonyl) pyridinium chloride (compound 26);

[0058] 1-(2-phenylamino-2-oxoethyl)-3-((4-methylphenyl) sulfonyl hydrazino carbonyl)pyridinium chloride (compound 27);

[0059] 1-(2-phenyl-2-oxoethyl)-3-(2-(benzoyloxy)ethyloxy carbonyl) pyridinium bromide (compound 28);

[0060] 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenylcarbonyl hydrazino carbonyl) pyridinium bromide (compound 29);

[0061] 1-(2-ethoxy-2-oxoethyl)-3-((phenylethyl)sulfonyl hydrazino carbonyl)pyridinium bromide (compound 30);

[0062] 1-(2-phenyl-2-oxoethyl)-3-((phenylmethyl)sulfonyl hydrazino carbonyl) pyridinium bromide. (compound 31);

[0063] N,N′-bis[3-carbonyl-1-(2-furan-2′-yl-2-oxoethyl) pyridinium]hydrazine dibromide. (Compound No: 32);

[0064] N,N′-bis[3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl) pyridinium]hydrazine dichloride. (Compound No: 33);

[0065] 1-(2-thien-2′-yl-2-oxoethyl)-3-((2-(1-oxo-3-cyclohexyl)-propyl)-hydrazino carbonyl)-pyridinium bromide. (Compound No: 34);

[0066] 1-(2-phenylamino-2-oxo ethyl)-3-({2-(1-oxo -3-cyclohexyl)-propyl}-hydrazinocarbonyl}-pyridinium bromide. (Compound No: 35);

[0067] 1-(2-thien-2′-yl-2-oxoethyl)-3-[2-(benzoyloxy)ethylamino carbonyl]-pyridinium bromide (Compound No: 36);

[0068] 1-(4-ethoxy-2,4-dioxobutyl)-3-(2-(benzoyloxy)ethylamino carbonyl)-pyridinium chloride. (Compound No: 37);

[0069] 1-(2′,4′-dichlorophenyl-2-oxoethyl)-3-(2-methoxyethyl aminocarbonyl)-pyridinium bromide. (Compound No: 38);

[0070] N,N′-bis-[3-carbonyl-1-(2-cyclopropylamino-2-oxoethyl) pyridinium]hydrazine dichloride. (Compound No: 39);

[0071] 1-(2-cyclopropylamino-2-oxoethyl)-3-(2-methoxyethylaminocarbonyl)-pyridinium chloride. (Compound No: 40);

[0072] N-N′-bis[3-carbonyl-1-(2-isopropylamino-2-oxoethyl) pyridinium]hydrazine dichloride. (Compound No: 41);

[0073] 1-(2-thien-2′yl-2-oxoethyl)-3-(2-(2-chloro-3-pyridoylhydrazinocarbonyl)-pyridinium chloride. (Compound No: 42);

[0074] 1-(2-isopropylamino-2-oxoethyl)-3-(2-methylsulfonylhydrazinocarbonyl)-pyridinium chloride. (Compound No: 43);

[0075] 1-(2-(1-pyrrolidinyl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride. (Compound No: 44);

[0076] 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride. (Compound No: 45);

[0077] N,N′-bis[3-carbonyl-1-(2-hydroxy-2-oxoethyl)pyridinium]hydrazine dichloride (Compound No: 46);

[0078] 1-(2-thien-2′-yl-2-oxoethyl)-3-((2-methoxy ethyl) amino carbonyl)-5-bromo pyridinium chloride (Compound No: 47);

[0079] 1-(2-thien-2′-yl-2-oxoethyl)-3-[1-oxo-1-(2-methoxy carbonyl)pyridyl]hydrazino pyridinium chloride. (Compound No: 48);

[0080] 1-[1-(2-thien-2′-yl-2-oxoethyl)-6-methyl-3-carbonyl pyridinium]-2-[1-(2-Thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium]hydrazine dichloride(compound no: 49).

[0081] 1-(2-thien-2′-yl-2-oxoethyl)-3-(isopropylsulfonyl hydrazino carbonyl) pyridinium bromide(compound no: 50).

[0082] 1-(2-(4-benzyl piperidin-1-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride(compound no: 51).

[0083] 1-(2-(2-ethoxy carbonyl pyrrolidin-1-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride. (compound no: 52).

[0084] 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl)-5-bromo pyridinium bromide. (compound no: 53).

[0085] 1-(2-thien-2′-yl-2-oxoethyl)-3-(ethoxycarbonyl hydrazino carbonyl) pyridinium bromide. (compound no: 54).

[0086] 1-(2-(5-chlorothien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide (compound no: 55).

[0087] N,N′-bis[3-carbonyl-1-(2-(4-nitrothien-2-yl)-2-oxoethyl)pyridinium]hydrazine dichloride. (compound no: 56).

[0088] 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl)-6-methyl pyridinium bromide. (compound no: 57).

[0089] N,N′-bis[3-carbonyl-1-(2-(5-methylthien-2-yl)-2-oxoethyl) pyridinium]hydrazine dichloride. (compound no: 58).

[0090] N,N′-bis[3-carbonyl-1-(2-(2-ethoxycarbonyl pyrrolidin-1-yl)-2-oxoethyl) pyridinium] hydrazine dichloride. (compound no: 59).

[0091] 1-[1-(2-thien-2′-yl-2-oxoethyl)-5-aminocarbonyl-3-carbonyl pyridinium]-2-[1-(2-Thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium]hydrazine dichloride (compound no: 60).

[0092] 1-(2-(4-carbethoxy-thiazolidin-3-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride (compound no: 61).

[0093] N,N′-bis[3-carbonyl-1-(2-(5-chlorothien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride. (compound no: 62).

[0094] 1-(2-(5-methylthien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride (compound no: 63).

[0095] 1-(2-(4-nitrothien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide. (compound no: 64).

[0096] 1-(2-phenylamino-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium chloride (compound no: 65).

[0097] 1-(2-phenylamino-2-oxoethyl)-4-[2-(benzoyloxy) ethylamino carbonyl] pyridinium chloride (compound no: 66).

[0098] 1-2-(5-nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride (compound no: 67).

[0099] 1-(2-thien-2′-yl-2-oxoethyl)-3-(fuoromethanesulfonyl hydrazino carbonyl)-pyridinium bromide. (compound no. 68).

[0100] 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide (compound no. 69).

[0101] 1-(2-thien-2′-yl-2-oxoethyl)-3-(p-methoxy phenyl sulfonyl hydrazino carbonyl) pyridinium bromide (compound no. 70).

[0102] 1-(2-ethoxy-2-oxoethyl)-3-(phenyl aminocarbonyl hydrazino carbonyl) pyridinium bromide (compound no. 71).

[0103] 1-(2-ethoxy-2-oxoethyl)-3-(p-toluene sulfonyl hydrazino carbonyl) pyridinium bromide (compound no. 72).

[0104] 1-(2-phenyl-2-oxoethyl)-3-(phenylamino carbonyl hydrazino carbonyl) pyridinium bromide (compound no. 73).

[0105] 1-(2-phenylamino-2-oxoethyl)-3-(benzyl sulfonyl hydrazino carbonyl) pyridiniumchloride. (compound no. 74).

[0106] (2-phenyl-2-oxoethyl)-4-(methanesulfonyl hydrazino carbonyl) pyridinium bromide (compound no. 75).

[0107] 1-(2-phenyl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide. (compound no. 76).

[0108] 1-(2-ethoxy-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide (compound no. 77).

[0109] 1-(2-ethoxy-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide. (compound no. 78).

[0110] 1-(2-phenyl-2-oxoethyl)-3-(p-methoxyphenyl sulfonyl hydrazino carbonyl) pyridinium bromide. (compound no. 79).

[0111] 1-(2-phenyl-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide. (compound no. 80).

[0112] 1-(2-ethoxy-2-oxoethyl)-4-(p-methanesulfonyl hydrazino carbonyl) pyridinium bromide. (compound no. 81).

[0113] In place of specific halide salts of the compounds listed above, these compounds may also be in the form of other pharmaceutically acceptable salts falling within the definition of X as given above. The words “and pharmaceutically acceptable salts thereof” as used herein following the names of specific compounds of general formula (I) of the invention means that such compounds encompass other pharmaceutically acceptable salts falling within the definition of X. TABLE 1A Representative Pyridinium derivatives (having m as 0 or 1 and —COR₁ at position 3) Com- pound R₁ —R₂ —R₃ —X 1 Structure (a) — phenyl Br 2 Structure (b) — OEt Br 3 Structure (c) — 2,4- Br dichlorophenyl 4 NHNH-(2-pyridyl) — OEt Br 5 NHNHSO₂CH₃ — 2-thienyl Br 6 Structure (d) — 2-thienyl Br 7 NHCH₂CH₂OCOPh — OEt Br 8 NHCH₂CH₂OCOPh — 2,4- Br dichlorophenyl 9 NHNH-(2-pyridyl) — 2-thienyl Br 10 NHNH-(2-pyridyl) — phenyl Br 11 NHNH₂ — phenyl Br 12 NHNHSO₂CH₃ — phenyl Br 13 NHNHSO₂CH₃ — OEt Br 14 NHNH—SO₂phenyl — phenyl Br 15 NHNH—SO₂phenyl 2-Cl phenyl Br 16 OCH₂CH₂OCOCH₃ — phenyl Br 17 OCH₂CH₂OCOPh — OEt Br 21 —NHNH—SO₂Ph — OEt Br 22 —OCH₂CH₂OCH₃ — 2,4- Br dichlorophenyl 23 —NHCH₂CH₂OCOPh — NH phenyl CI 24 —NHNHCONHPh — 2-thienyl Br 25 NHCH₂CH₂OCOCH₃ — phenyl Br 26 NHNHSO₂ Ph — NH phenyl CI 27 NHNHSO₂ Ph(4-CH₃) — NH phenyl CI 28 OCH₂CH₂OCOPh — phenyl Br 29 —NHNHCOPh — 2-thienyl Br 30 NHNHSO₂CH₂Ph — OEt Br 31 NHNHSO₂CH₂Ph — phenyl Br 32 Structure (e) — 2-furyl Br 33 Structure-(f) — 2-thienyl Cl 34 NHNHCOCH₂CH₂- — 2-thienyl Br cyclohexyl 35 NHNHCOCH₂CH₂- — NH-phenyl Cl cyclohexyl 36 NHCH₂CH₂OCO- — 2-thienyl Br phenyl 37 NHCH₂CH₂OCO- — CH₂CO₂-ethyl Cl phenyl 38 —NHCH₂CH₂OCH₃ — -2,4- Br dichlorophenyl 39 Structure-(g) — NH-cyclopropyl Cl 40 —NHCH₂CH₂OCH₃ — NH-cyclopropyl Cl 41 Structure-(h) — NH-isopropyl Cl 42 Structure-(i) — 2-thienyl Cl 43 NHNHSO₂CH₃ — NH-isopropyl Cl 44 NHNHSO₂CH₃ — 1-pyrrolidinyl Cl 45 NHNHSO₂CH₃ — 2-thienyl Cl 46 Structure-(j) — —OH Cl 47 NHCH₂CH₂OCH₃ — 2-thienyl Cl 48 Structure-(k) — 2-thienyl Cl 49 Structure-(l) — 2-thienyl Cl 50 —NHNHSO₂isopropyl — 2-thienyl Br 51 —NHNHSO₂CH₃ — Structure (m) Cl 52 —NHNHSO₂CH₃ — Structure (n) Cl 53 —NHNHSO₂CH₃ 5- 2-thienyl Br Bromo 54 —NHNHCOC₂H₅ — 2-thienyl Br 55 —NHNHSO₂CH₃ — 5-chloro- Br 2-thienyl 56 Structure (o) — 4-nitro- Cl 2-thienyl 57 —NHNHSO₂CH₃ 6- 2-thienyl Br methyl 58 Structure (p) — 5-methyl- Cl 2-thienyl 59 Structure (q) — Structure (n) Cl 60 Structure (r) — 2-thienyl Cl 61 —NHNHSO₂CH₃ — Structure (s) Cl 62 Structure (t) — 5-chloro- Cl 2-thienyl 63 —NHNHSO₂CH₃ — 5-methyl- Cl 2-thienyl 64 —NHNHSO₂CH₃ — 4-nitro- Br 2-thienyl 65 —NHNHPh — —NHPh Cl 67 —NHNHSO₂CH₃ — 5-nitro- Cl 2-thienyl 68 —NHNHSO₂CF₃ — 2-thienyl Br 69 —NHNHPh — 2-thienyl Br 70 —NHNHSO₂-4-methoxy- — 2-thienyl Br Phenyl 71 —NHNHCONHPh — —OEt Br 72 —NHNHSO₂-4-methyl- — —OEt Br Phenyl 73 —NHNHCONHPh — Ph Br 74 —NHNHSO₂CH₂Ph — —NHPh Cl 76 —NHNHPh — Ph Br 78 —NHNHPh — —OEt Br 79 —NHNHSO₂-4-methoxy- — Ph Br Phenyl (a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

(i)

(j)

Structure (k)

Structure (l)

Structure (m)

Structure (n)

Structure (o)

Structure (p)

Structure (q)

Structure (r)

Structure (S)

Structure (t)

[0114] TABLE 1B Representative Pyridinium derivatives (having m as 0 and —COR₁ at position 4) Compound —R₁ —R₂ —R₃ —X 18 NHCH₂CH₂OCOPh — 2-thienyl Br 19 NHNHSO₂Ph — OEt Br 20 NHNHSO₂Ph — NH CI phenyl 66 —NHCH₂CH₂OCOPh — —NHPh Cl 75 —NHNHSO₂CH₃ — —Ph Br 77 —NHCH₂CH₂OCOPh — —OEt Br 80 —NHCH₂CH₂OCOPh — —Ph Br 81 —NHNHSO₂CH₃ — —OEt Br

[0115] According to the embodiment of the present invention, the present compounds are used for the treatment of diabetic complications, and aging related vascular and neurovascular complications including kidney disease, nerve damage, atherosclerosis, retinopathy, inflammatory discorders, immunological disorders, oxidative stress, dermatological conditions, and cosmetic conditions including colouration of teeth occurring due to the higher levels of preformed AGE. The increased levels of preformed AGE can be brought under control by breaking the AGE products using compounds mentioned in the invention.

[0116] The invention also provides a process for the preparation of novel compounds of the pyridinium series.

[0117] The said process for the preparation of compound 1, comprises, adding a solution of phenacyl bromide in isopropanol to N,N′-bis-(nicotinyl)hydrazine dissolved in methanol, refluxing for six hours, cooling, filtering the precipitated solid, washing the solid with hot ethyl acetate and finally purifying the solid with 20 ml of methanol:ethyl acetate (3:1) to yield the desired compound.

[0118] Similarly, the other novel compounds of general formula I, are prepared from properly substituted pyridine derivatives followed by quarternization with appropriate reagent by refluxing in alcoholic solvents like, methanol, ethanol, propanol, etc and high boiling solvents like toluene or xylene etc, for 6-48 hrs. to give the desired compounds.

[0119] The examples of substituted pyridine derivatives which can be used for preparation of specific compounds of the invention are given below:

[0120] 1. N,N′-bis(nicotinyl)hydrazine

[0121] 2. 3-[(2-pyridyl)hydrazinocarbonyl]pyridine

[0122] 3. 3-[(2-methanesulfonyl)hydrazinocarbonyl]pyrridine

[0123] 4. 3-[(2-benzoyloxy)ethylaminocarbonyl]pyridine

[0124] 5. 3-[(2-phenylsulfonyl)hydrazinocarbonyl]pyridine

[0125] 6. 3-[(2-acetoxy)ethyloxycarbonyl]pyridine

[0126] 7. 3-[(2-benzoyloxy)ethyloxycarbonyl]pyridine

[0127] 8. 3-[(2-methoxy)ethyloxycarbonyl]pyridine

[0128] 9. 3-[(2-phenylaminocarbonyl)hydrazinocarbonyl]pyridine

[0129] 10. 3-[(2-acetoxy)ethylaminocarbonyl]pyridine

[0130] 11. 3-[(2-(4-methylphenyl sulfonylhydrazinocarbonyl))]pyridine

[0131] 12. 3-[(2-benzoyl)-hydrazino carbonyl]pyridine

[0132] 13. 3-[(2-phenylmethane sulfonyl) hydrazino carbonyl]pyridine

[0133] 14. 3-[(2-(3-cyclohexylpropanoyl) hydrazino carbonyl]pyridine

[0134] 15. 3-[(2-methoxy)ethylaminocarbonyl]pyrridine

[0135] 16. 3-[1-oxo-1-(2-methoxycarbonyl)pyridyl]hydrazino pyridine

[0136] The examples of quaternizing agents which may be used in the reaction are given below:

[0137] 1. 2-bromoacetyl thiophene

[0138] 2. 2-chloroacetyl thiopene

[0139] 3. phenacylbromide

[0140] 4. phenacylchloride

[0141] 5. 2,4-dichloropheanacylbromide

[0142] 6. N-phenyl chloroacetamide

[0143] 7. N-cyclopropyl chloroacetamide

[0144] 8. ethylbromoacetate

[0145] 9. bromo acetylfuran

[0146] 10. N-isopropylchloroacetamide

[0147] 11. N-chloroacetyl-2-pyrrolidinone

[0148] 12. chloroacetic acid

[0149] In-vitro Screening for AGE-breaking Activity

[0150] The in vitro AGE formation, studied in the laboratory, by incubating reducing sugar glucose, with protein bovine serum albumin, resulted in browning of solution and increase in the fluorescence. Fluorescence was used as the criteria to monitor the increased AGE formation.

EXAMPLE 1 AGE Breaker Activity has Been Confirmed by the Screening Procedure as Mentioned Below

[0151] Materials:

[0152] Bovine serum albumin (fraction V) (BSA)

[0153] Glucose, analytical grade

[0154] Phosphate buffered saline (PBS)

[0155] Equipment:

[0156] Microplate ELISA Reader—Spectramax Plus (Molecular Devices, USA)

[0157] Microplate washer, (Bio-Tec Instruments, USA) pH meter

[0158] Methods of experiment: Elisa (Enzyme Linked Immunosorbent Assay)

[0159] 160 mg/ml of protein, bovine serum albumin, BSA and 1.6M glucose sugar were dissolved in phosphate buffered saline, PBS. Sodium azide was added at 0.02% concentration as a preservative. The solution was filtered asceptically through a 0.22 μM filter and kept for aging at 37° C. for 16 weeks. After 16 weeks the solution was dialyzed against PBS, aliquoted and stored at −20° C.

[0160] To determine the AGE breaking activity, 10 μg/ml of the 16 weeks AGE-BSA was incubated with different concentrations of the test compounds at 37° C. for 24 hours and AGE breaking activity of the test compounds by ELISA was determined.

[0161] ELISA was performed as follows:

[0162] 1. Different concentrations of 16 weeks AGE-BSA were coated on a microtitre plate as standard. Each concentration is coated in triplicates.

[0163] 2. The test samples were coated on microtitre plate at a concentration of 5 ng. to 20 ng per well in triplicates.

[0164] 3. The plate was incubated at 37° C. for one hour.

[0165] 4. After incubation the plate was washed with PBST (PBS with 0.05% Tween 20).

[0166] 5. Blocking with 5% skimmed milk in PBS at 37° C. for one hour was done.

[0167] 6. The plate was washed with PBST.

[0168] 7. Primary antibody against AGE-BSA was added and the plate is incubated at 37° C. for one hour.

[0169] 8. The plate was washed with PBST

[0170] 9. Secondary antibody anti rabbit HRPO (Horse-Radish Per Oxidase) conjugate was added and the plate is incubated at 37° C. for one hour.

[0171] 10. The plate was washed with PBST.

[0172] 11. Colour development with OPD (orthophenylenediamine dihydrochloride) and hydrogen peroxide was done.

[0173] 12. OD (optical density) at (450 nm reading-620 nm reading) was measured after incubation at 37° C. for 15 minutes with Microplate ELISA Reader.

[0174] The breaker activity of the compounds were determined by the following formula: ${\% \quad {Breaker}\quad {activity}} = {\frac{{{OD}_{450 - 620}{Control}} - {{OD}_{450 - 620}{Test}}}{{OD}_{450 - 620}{Control}} \times 100}$

[0175] OD₄₅₀₋₆₂₀Control=Absorbance of 20 ng AGE-BSA after incubation at 37° C. for 24 hours without test compound

[0176] OD₄₅₀₋₆₂₀Test=Absorbance of 20 ng AGE-BSA after incubation at 37° C. for 24 hours with required concentration of test compound

[0177] Using specific examples, the % AGE breaking activity was calculated and recorded in Table 2. TABLE 2 Sample Concentration % Breakage PTB 10 mM 27 20 mM 47 Compound 1 5 mM 13 Compound 4 10 mM 30 Compound 5 10 mM 16 50 mM 68 Compound 6 5 mM 53 Compound 7 20 mM 36 Compound 16 10 mM 16 Compound 17 10 mM 19 Compound 22 10 mM 13 25 mM 41 Compound 23 10 mM 37 25 mM 90 Compound 32 10 mM 14 Compound 33 5 mM 20 Compound 38 5 mM 17.66 Compound 39 5 mM 22.8 Compound 40 10 mM 12.38 Compound 42 10 mM 12.51 Compound 43 10 mM 10.85 Compound 45 10 mM 17.53 Compound 47 10 mM 32.38 Compound 49 2.5 mM 85.67 Compound 50 10 mM 31.45 Compound 51 10 mM 20.94 Compound 52 10 mM 25.34 Compound 53 2.5 mM 29.36 Compound 54 10 mM 33.43 Compound 55 10 mM 40.85 Compound 56 10 mM 75.92 Compound 57 1.0 mM 77.69 Compound 58 10 mM 81.95 Compound 59 10 mM 20.31 Compound 60 1 mM 95.36 Compound 61 10 mM 25.06 Compound 62 10 mM 78.41 Compound 63 10 mM 25.17 Compound 64 10 mM 60.94 Compound 65 2.5 mM 68.35 Compound 66 10 mM 19.07 Compound 67 1 mM 42.01 Compound 68 10 mM 92.64

[0178] Hence compounds 4, 6, 23, 33, 39, 47, 49, 50, 53-58, 60, 62, 64, 65, 67 and 68 have superior AGE breaking activity compared to PTB, of which the potency of compounds 49, 56-58, 60 62, 64, 65, 67 and 68 are significantly much higher.

[0179] In-vivo Screening for AGE-breaking Activity:

[0180] The test compounds were studied for their beneficial effects on diabetic neuropathy and nephropathy in a rat model of diabetes. The rats were divided into three groups. The first group consisted of age matched untreated non-diabetic animals. The second group consisted of diabetic controls and the third group was the diabetic group treated with the test compound. Each treatment group had its own corresponding control and diabetic groups. The second and third groups were treated with Streptozotocin (STZ) at 60 mg/kg for the induction of diabetes. After completion of 12 weeks of diabetes the rats were treated with the test compound daily (doses shown in table) for a period of 8 weeks. At the end of the treatment the creatinine clearances and nerve conduction velocities (NCV) of the animals were estimated. Creatinine clearances of the rats were estimated as follows ${{Creatinine}\quad {clearance}} = {\frac{{Concentration}\quad {of}\quad {creatinine}\quad {in}\quad {the}\quad {urine}}{{Concentration}\quad {of}\quad {creatinine}\quad {in}\quad {the}\quad {blood}} \times {ml}\quad {urine}\quad {{passed}/{{minute}.}}}$

[0181] The creatinine clearance in untreated diabetic group was compared with the treated group and the percentage improvements are shown in the Table 3.

[0182] The nerve conduction velocity was measured using a modified method of Biro et al 1998. Briefly under ether anesthesia the sciatic and tibial nerves were electrically stimulated at the sciatic notch or ankle, respectively. Electromyograms (EMG's) recorded from the plantar muscles consisted of two components: (1) the short latency direct motor response (M) and the monosynaptically elicited long-latency sensory response (H, Hoffmann reflex). Latency and the duration of the M responses were measured and the motor nerve conduction velocity (MNCV) was calculated as follows: ${MNCV} = {\frac{{Distance}\quad {between}\quad {the}\quad {sciatic}\quad {and}\quad {tibial}\quad {stimulation}\quad {points}}{{Differences}\quad {of}\quad {the}\quad {latency}\quad {for}\quad M_{sciatic}\quad {and}\quad M_{tibial}}.}$

[0183] The percentage improvement in the nerve conduction velocities in the group treated with the test compounds was calculated as follows: ${\% \quad {Improvement}\quad {in}\quad {the}\quad {{NCV}'}s} = {\frac{{{NCV}\quad {of}\quad {the}\quad {treated}\quad {group}} - {{NCV}\quad {of}\quad {the}\quad {diabetic}\quad {group}}}{{{NCV}\quad {of}\quad {the}\quad {control}\quad {group}} - {{NCV}\quad {of}\quad {the}\quad {diabetic}\quad {group}}}.}$

TABLE 3 Effect of compound Nos 33 and 39 on the creatinine clearance and nerve conduction velocities: Compound No.33 Compound No.39 Parameters (7.5 mg/kg, b.i.d.) (6.0 mg/kg, b.i.d.) % Increase in creatinine 103.0 5.0 clearance % Increase in the NCV 60.0 58.4

[0184] The results show that compounds of this class have beneficial effects on creatinine clearance and nerve conduction velocities.

[0185] Discussion of the Test Results:

[0186] All the test compounds mentioned in the current application have shown an invitro AGE-breaker effect. Under conditions of chronic hyperglycemia in rats there is a spontaneous non-enzymatic reaction between glucose, lipids and proteins that leads to the formation of advanced glycosylation end products. In this animal model decreased creatinine clearance and decreased nerve conduction velocity have been demonstrated. These changes are related to damage to renal and neuronal tissues. During chronic NIDDM patients, there is a decrease in the creatinine clearances as a manifestation of the diabetes induced renal damage. One of the major factors contributing to renal damage is the glycation of the long-lived proteins in the kidney. It is well recognized that there is a decrease in the nerve conduction velocities in chronic diabetic subjects, which is a manifestation of neuropathy. Breaking of cross-linked proteins in the neuronal tissues and associated vasculature could lead to an improvement in the neuronal function.

[0187] The compounds of the present invention have shown a functional improvement both in terms of the improvement in the creatinine clearance and an improvement in the nerve conduction velocities. The evidences stated above clearly demonstrate that these compounds could play a major role in the prevention and treatment of various diabetic and aging related complications like nephropathy and neuropathy.

[0188] The following examples give method of preparation of the specific novel compounds of the invention as given in Table 1. The following compounds suggested are by way of example alone and in no way restrict the invention.

EXAMPLE 2 Preparation of N,N′-bis[3-carbonyl-1-(2-phenyl-2-oxoethyl) pyridinium] hydrazine dibromide (compound 1)

[0189] To a boiling solution of N,N′-bis-(nicotinyl)hydrazine (1.21 g., 0.005 mol.) in methanol (20 ml.), a solution of phenacyl bromide (1.99 g., 0.01 mol.) in isopropanol (10 ml.) was added and the reaction mixture was refluxed for 6 hrs. The reaction mixture was concentrated under vacuum (˜10 ml.) and filtered. The obtained residue was washed with hot ethylacetate and then the isolated solid was powdered. It was recrystallised from a mixture of methanol and ethylacetate (3:1, 20 ml) to afford a pale yellow solid.

[0190] Yield: 60% m.p.: 260-262° C. (decomp.) IR(KBr, cm⁻¹): 1696 and 1680 ¹H NMR (DMSOd₆, 400 MHz) δ: 11.65(2H,s), 9.56(2H,s), 9.21-9.16(4H,m), 8.49-8.45 (2H,m), 8.08-8.05 (4H,d), 7.81-7.77(2H,m), 7.68-7.64 (4H,m), 6.58 (4H,s) Mass (m/z): 479, 480

[0191] According to the above mentioned procedure the following compounds are synthesized by reacting the corresponding pyridine derivatives with appropriate reagents by refluxing in methanol, ethanol, propanol, toluene or xylene for 6-48 hrs. to get the desired compounds:

EXAMPLE 3 N,N′-Bis[3-carbonyl-1-(2-ethoxy-2-oxoethyl) pyridinium]hydrazine dibromide (compound 2)

[0192] Yield: 47% m.p.: 180-182° C. (decomp.) IR(KBr, cm⁻¹): 1744, 1664 ¹H NMR (DMSOd₆, 400 MHz) δ: 11.65 (2H,s), 9.62 (2H,s), 9.28-9.26 (2H,d), 9.17-9.15 (2H,d), 8.47-8.44 (2H,m), 5.77 (4H,s), 4.26 (4H,q), 1.27 (6H,t) Mass (m/z): 415, 416

EXAMPLE 4 N,N′-Bis[3-carbonyl-1-(2-(2,4-dichlorophenyl)-2-oxoethyl) pyridinium] hydrazine dibromide (compound 3)

[0193] Yield: 24% m.p.: 225-227° C. (decomp.) IR(KBr, cm⁻¹): 1702, 1666 ¹H NMR (DMSOd₆, 400 MHz) δ: 11.69 (2H,s), 9.58 (2H,bs), 9.20-9.18 (4H,m), 8.49-8.47 (2H,m), 8.17-8.15 (2H,d), 7.92 (2H,bs), 7.78-7.76 (2H,d), 6.50 (4H,s) Mass (m/z): 615, 617, 618, 620.

EXAMPLE 5 1-(2-Ethoxy-2-oxoethyl)-3-(2-(2-pyridyl) hydrazinocarbonyl) pyridinium bromide (compound 4)

[0194] Yield: 16% m.p.: 210-212° C. IR (KBr, cm⁻¹): 3140, 3005, 1732 and 1690 ¹H NMR (DMSOd₆, 400 MHz) δ: 9.63 (1H,s), 9.27 (2H,d), 8.49-8.45 (1H,m) 8.13-8.07 (2H,m), 7.32-7.30 (1H,m), 7.12-7.11(1H,m), 5.77 (2H,s), 4.23 (2H,q), 1.25 (3H,t) Mass (m/z): 301, 302

EXAMPLE 6 1-(2-Thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide (compound 5)

[0195] Yield: 30% m.p.: 199-200° C. IR (KBr, cm⁻¹): 1714, 1673 ¹HNMR (DMSOd₆, 400 MHz) δ: 11.38 (1H,s), 9.97 (1H,s) 9.51 (1H,s), 9.16 (1H,d), 9.06-9.04 (1H,m), 8.43-8.39 (1H,m), 8.25-8.21 (2H,m), 7.43-7.41 (1H,t), 6.45 (2H,s), 3.08 (3H,s). Mass (m/z): 340, 341, 342

EXAMPLE 7 N,N′-Bis[3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl) pyridinium]hydrazine dibromide (compound 6)

[0196] Yield: 33% m.p.: 259-261° C. (decomp.) IR (KBr, cm⁻¹): 3330, 1702, 1674, 1655 and 1626 ¹H NMR (DMSOd₆, 400 MHz) δ: 11.59 (2H,s), 9.50 (2H,s), 9.15-9.08 (4H,m), 8.40-8.36 (2H,m), 8.17-8.14 (4H,m), 7.33(2H,t), 6.42 (4H,s) Mass (m/z): 491, 492.

EXAMPLE 8 1-(2-Ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethylaminocarbonyl) pyridinium bromide (compound 7)

[0197] Yield: 85% m.p.: 132-134° C. IR (KBr, cm⁻¹): 3210, 3067, 1726, 1687, 1656 ¹H NMR (DMSOd₆, 400 MHz) δ: 9.46 (1H,s), 9.37 (1H,t), 9.11(1H,t), 8.97 (1H,d), 8.33-8.29 (1H,m) 7.95-7.93 (2H,m), 7.63-7.59 (1H,m), 7.49-7.45 (2H,m), 5.65 (2H,s), 4.39 (2H,t), 4.19 (2H,q), 3.70-3.69 (2H,m), 1.20 (3H,t) Mass (m/z): 357, 358, 359

EXAMPLE 9 1-(2-(2′,4′-Dichlorophenyl)-2-oxoethyl)-3-(2-(benzoyloxy)ethyl aminocarbonyl) pyridinium bromide (compound 8)

[0198] Yield: 75% m.p.: 102-104° C. IR(KBr, cm⁻¹): 1703, 1685, 1675 ¹H NMR (DMSOd₆, 400 MHz) δ: 9.41-9.37 (2H,m), 9.03-8.98 (2H,m)8.34-8.30 (1H,m), 8.04 (1H,d), 7.91-7.89 (2H,m), 7.82 (1H,d), 7.68-7.65 (1H,m), 7.58-7.55 (1H,m), 7.43 (2H,t), 6.35 (2H,s), 4.36 (2H,t), 3.68-3.64 (2H,m) Mass (m/z): 457, 458, 459, 460, 461, 462

EXAMPLE 10

[0199] 1-(2-Thien-2′-yl-2-oxoethyl)-3-(2-(2-pyridyl) hydrazinocarbonyl) pyridinium bromide (compound 9)

[0200] Yield: 10% m.p.: 212-214° C. (decomp) IR(KBr, cm⁻¹): 1685, 1649 ¹H NMR (DMSOd₆, 400 MHz) δ: 11.21 (1H,bs), 9.59 (1H,s), 9.19 (2H,d), 8.44 (1H,t), 8.27-8.24 (2H,m), 8.08 (1H,bs), 7.62 (1H,bs), 7.44 (1H,t), 6.85-6.79 (2H,m), 6.50 (2H,s) Mass (m/z): 339, 340, 341

EXAMPLE 11 1-(2-Phenyl-2-oxoethyl)-3-(2-(2-pyridyl) hydrazinocarbonyl) pyridinium bromide (compound 10)

[0201] Yield: 4% m.p.: 190° C. (decomp) IR(KBr, cm⁻¹): 1683, 1670, 1648 ¹H NMR (DMSOd₆, 400 MHz) δ: 11.14 (1H,bs), 9.53 (1H,s), 9.18-9.13 (2H,m), 8.45-8.42 (1H,t), 8.08-8.06 (3H,m), 7.80 (1H,t), 7.67 (2H,t), 7.62-7.55 (1H,m), 6.83-6.76 (2H,m), 6.54 (2H,s) Mass (m/z): 333, 334, 335

EXAMPLE 12 1-(2-Phenyl-2-oxoethyl)-3-(hydrazinocarbonyl) pyridinium bromide (compound 11)

[0202] Yield: 15% m.p.: 215-216° C. IR(KBr, cm⁻¹): 1695, 1680 ¹HNMR (DMSO₆, 400 MHz) δ: 10.25 (1H,s) 9.65 (1H,s), 9.35-9.32 (2H,m), 8.90-8.88 (1H,m) 8.50-8.46 (2H,d), 8.21-8.17 (1H,m), 8.05-8.07 (2H,m), 6.50 (2H,s), 4.45 (2H,s). Mass (m/z): 256, 257.

EXAMPLE 13 1-(2-Phenyl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide (compound 12)

[0203] Yield: 35% m.p.: 227-228° C. IR(KBr, cm⁻¹): 1710, 1702

[0204]1HNMR (DMSOd₆, 400 MHz) δ: 11.30, (1H,s), 9.88 (1H,s), 9.41 (1H,s), 9.06-9.05 (1H,d) 8.98-8.96 (1H,d), 8.34-8.31 (1H,m), 7.97 (2H,d), 7.72-7.69 (1H,t), 7.59-7.56 (2H,t), 6.44 (2H,s), 2.99 (3H,s) Mass (m/z): 334, 335

EXAMPLE 14 1-(2-Ethoxy-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide (compound 13)

[0205] Yield: 38% m.p.: 75-76° C. IR(KBr, cm⁻¹): 1739, 1697 ¹HNMR (DMSOd₆, 400 MHz) δ: 11.39 (1H,s), 9.96 (1H,s), 9.56 (1H,s), 9.23 (1H,d), 9.06 (1H,d), 8.40 (1H,t), 5.75 (2H,s), 4.27-4.22 (2H,q), 3.08 (3H,s), 1.26 (3H,t) Mass (m/z): 301, 302, 303

EXAMPLE 15 1-(2-Phenyl-2-oxoethyl)-3-(phenylsulfonylhydrazino carbonyl) pyridinium bromide (compound 14)

[0206] Yield: 28% m.p.: 187-188° C. (dec.) IR(KBr, cm⁻¹): 1700, 1633 ¹HNMR (DMSOd₆, 400 MHz) δ: 11.38 (1H,s), 10.45 (1H,s), 9.33(1 H,s), 9.13-9.12 (1H,d), 8.95 (1H, d), 8.38 (1H,t), 8.05 (2H,d), 7.89 (2H,d), 7.80 (1H,t), 7.66 (3H,t), 7.57 (2H,t), 6.50 (2H,s). Mass (m/z): 396, 397, 398

EXAMPLE 16 1-(2-Phenyl-2-oxoethyl)-2-chloro-3-(phenylsulfonylhydrazino carbonyl) pyridinium bromide (compound 15)

[0207] Yield: 23% m.p.: 247-250° C. (decomp) IR(KBr, cm⁻¹): 1685, 1679, ¹HNMR (DMSOd₆, 400 MHz) δ: 11.12 (1H,s), 9.49 (1H,s), 9.07-9.03(1H,m), 8.44 (1H, t), 8.07 (2H,d), 7.80 (1H,t), 7.67 (2H,t), 7.18 (2H,t), 6.87 (2H,d), 6.77 (1H,t), 6.50 (2H,s). Mass (m/z): 430, 431, 432

EXAMPLE 17 1-(2-Phenyl-2-oxoethyl)-3-(2-(acetoxy) ethyloxy carbonyl) pyridinium bromide (compound 16)

[0208] Yield: 40% m.p.: 152-153° C. IR(KBr, cm⁻¹): 1737, 1691, 1635 ¹HNMR (DMSOd₆, 400 MHz) δ:9.63(1H,s), 9.24(1H,d), 9.12(1H,d), 8.43(1H,t), 8.07(2H,d), 7.80(1H,t), 7.67(2H,t), 6.59(2H,s), 4.62-4.60 (2H,m), 4.39-4.37(2H,m), 2.03 (3H,s) Mass (m/z): 328, 329

EXAMPLE 18 1-(2-Ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethyloxycarbonyl) pyridinium bromide (compound 17)

[0209] Yield: 35% m.p.: 142-143° C. IR(KBr, cm⁻¹): 1736, 1718, 1636 ¹HNMR (DMSOd₆, 400 MHz) δ: 9.60(1H,s), 9.20-9.18(1H,d), 9.04-9.02(1H,d), 8.33-8.29(1H,m), 7.90-7.88(2H,d), 7.58-7.57(1H,m), 7.46-7.42(2H,m), 5.67(2H,s), 4.71-4.68(2H,m), 4.58-4.56(2H,m), 4.15(2H,q), 1.16(3H,t) Mass (m/z): 358, 359, 360

EXAMPLE 19 1-(2-Thien-2′-yl-2-oxoethyl)-4-(2-(benzoyloxy) ethylaminocarbonyl) pyridinium bromide (compound 18)

[0210] m.p.: 210-211° C. IR(KBr, cm⁻¹): 1723, 1680, 1668 ¹HNMR (DMSOd₆, 400 MHz) δ: 9.52 (1H,t), 9.14 (2H,d), 8.50 (2H,d), 8.25-8.21 (2H,m), 8.01-7.99 (2H,d), 7.67 (1H,t), 7.55-7.51 (2H,m), 7.42-7.40 (1H,m), 6.42 (1H,s) 4.47-4.45 (2H,t), 3.77-3.73 (2H, m). Mass (m/z): 395, 396

EXAMPLE 20 1-(2-Ethoxy-2-oxoethyl)-4-(phenylsulfonyl hydrazino carbonyl) pyridinium bromide (compound 19)

[0211] Yield: 60% m.p.: 171-173° C. IR (KBr, cm⁻¹): 1745, 1685, 1645. ¹HNMR (DMSOd₆, 400 MHz) δ: 11.41 (1H, s), 10.39 (1H, s), 9.10 (2H, d), 8.27 (2H, d), 7.82-7.80 (2H, d), 7.60-7.57 (1H, t), 7.50-7.46 (2H, t), 5.63 (2H, s), 4.18-4.12 (2H, q), 1.19-1.15 (3H, t). Mass (m/z): 364, 365, 366

EXAMPLE 21 1-(2-Phenylamino-2-oxoethyl)-4-(phenylsulfonyl hydrazino carbonyl) pyridinium chloride (compound 20)

[0212] Yield: 10% m.p.: 225-227° C. IR (KBr, cm⁻¹): 1693, 1642, 1592 ¹HNMR(DMSOd₆, 400 MHz) δ: 11.55 (1H, s), 10.99 (1H, s), 10.49 (1H, s), 9.20 (2H, d), 8.34 (2H, d), 7.89 (2H,d), 7.73-7.64 (1H, t), 7.61-7.56 (4H, m), 7.37-7.33 (2H, t), 7.12-7.09 (1H, t), 5.73 (2H, s). Mass (m/z): 411, 412, 413, 414

EXAMPLE 22 1-(2-Ethoxy-2-oxoethyl)-3-(phenylsulfonylhydrazino carbonyl) pyridinium bromide (compound 21)

[0213] Yield: 75% m.p.: 145-147° C. IR(KBr cm⁻¹): 1744, 1713, 1633 ¹HNMR (DMSOd₆, 400 Mz)67 : 11.27(1H,s), 10.36 (1H, s), 9.28(1H,s), 9.09(1H,d), 8.83(1H,d), 8.27-8.24 (1H,m), 7.82-7.79 (2H,m), 7.58 (1H,t), 7.48 (2H, t), 5.59 (2H, s), 4.17-4.12 (2H, q), 1.16(3H,t). Mass (m/z): 364, 365, 366

EXAMPLE 23 1-(2-(2′,4′-Dichlorophenyl)-2-oxoethyl)-3-(2(methoxy)ethyloxycarbonyl) pyridinium bromide (compound 22)

[0214] Yield: 25% m.p.: 156-158° C. IR (KBr, cm⁻¹): 1731, 1706, 1640 ¹HNMR (DMSO d₆,400 MHz)δ: 9.61 (1H, s), 9.20(1H, d), 9.13 (1H, d), 8.45-8.41 (1H, m), 8.15 (1H, d), 7.92(1H, d), 7.78-7.76 (1H, m), 6.49 (2H, s), 4.56-4.54 (2H, m), 3.72-3.69 (2H, q), 3.31 (3H, s). Mass (m/z): 368, 369, 370, 371

EXAMPLE 24 1-(2-Phenylamino-2-oxoethyl)-3-(2-(benzoyloxyl) ethylaminocarbonyl) pyridinium chloride (compound 23)

[0215] Yield: 70% m.p.: 171-172° C. IR (KBr, cm⁻¹) 1720, 1692, 1668 ¹HNMR: (DMSOd₆, 400 MWz) 67 : 11.06 (1H, s), 9.67 (1H, t), 9.59 (1H, s), 9.20 (1H,d), 9.11 (1H, d), 8.36-8.32(1H, m), 8.00 (2H, d), 7.66-7.61 (3H, m), 7.51 (2H, t), 7.34 (2H, t), 7.10 (1H, t), 5.77 (2H,s), 4.45 (2H,t), 3.76-3.72 (2H, q). Mass (m/z): 404, 405, 406, 407

EXAMPLE 25 1-(2-Thien-2′-yl-2-oxoethyl)-3-(phenylaminocarbonyl hydrazinocarbonyl) pyridinium bromide (compound 24)

[0216] Yield: 30% m.p.: 202-204° C. IR (KBr, cm⁻¹): 1718, 1673 ¹HNMR: (DMSOd₆, 400 MHz) 67 : 11.03 (1H, s), 9.55 (1H, s), 9.18 (1H, d), 9.10 (1H, d), 9.00 (1H, s), 8.57 (1H,s), 8.46-8.42 (1H, t), 8.25-8.22 (2H, m), 7.47-7.45 (2H, d), 7.43-7.41 (1H, t), 7.29-7.25 (2H, t), 7.0-6.96 (1H, t), 6.46 (2H, s). Mass (m/z): 381, 382, 383

EXAMPLE 26 1-(2-Phenyl-2-oxoethyl)-3-(2-(acetoxy) ethylaminocarbonyl) pyridinium bromide (compound 25)

[0217] Yield: 55% m.p.: 186-188° C. IR (KBr, cm⁻¹): 1734, 1697, 1679 ¹HNMR (DMSOd₆, 400 MHz) δ: 9.47(1H,s), 9.36 (1H,t), 9.13-9.05 (2H, m), 8.42-8.38 (1H, m), 8.06 (2H, d), 7.80 (1H, t), 7.67 (2H, t), 6.54 (2H, s), 4.18 (2H,t), 3.61-3.57 (2H,q), 2.02 (3H,s). Mass (m/z): 327, 328, 329.

EXAMPLE 27 1-(2-Phenylamino-2-oxoethyl)-3-(phenyl sulfonyl hydrazino carbonyl) pyridinium chloride (compound 26)

[0218] Yield: 38% m.p.: 232-234° C. IR (KBr, cm⁻¹): 1689, 1636, 1596 ¹HNMR (DMSOd₆, 400 MHz) δ: 11.30 (1H, s), 10.80 (1H, s), 10.37 (1H, s), 9.29 (1H, s), 9.09 (1H, d), 8.81 (1H, d), 8.25-8.21 (1H, t), 7.82-7.80 (2H, d), 7.59-7.46 (5H, m), 7.28-7.24 (2H, t), 7.04-7.00 (1H, t), 5.62 (2H,s). Mass (m/z): 411, 412, 413, 414

EXAMPLE 28 1-(2-Phenylamino-2-oxoethyl)-3-((4-methylphenyl)sulfonyl hydrazino carbonyl) pyridinium chloride (compound 27)

[0219] Yield: 48% m.p.: 205-206° C. IR(KBr, cm⁻¹): 1712, 1681, 1632 ¹HNMR (DMSOd₆, 400 MHz) δ: 11.35 (1H, s), 10.86 (1H, s), 10.36 (1H, s), 9.38 (1H, s), 9.17 (1H, d), 8.90 (1H,d), 8.34-8.30 (1H, m), 7.78 (2H,d), 7.59 (2H, d), 7.37-7.33 (4H,m), 7.11 (1H,t), 5.70 (2H,s), 2.36 (3H,s). Mass (m/z): 425, 426, 427, 428

EXAMPLE 29 1-(2-Phenyl-2-oxoethyl)-3-(2-(benzoyloxy)ethyloxy carbonyl) pyridinium bromide (compound 28)

[0220] Yield: 35% m.p.: 132-134° C. IR (KBr, cm⁻¹): 1730, 1705, 1690 ¹HNMR (DMSOd₆, 400 MHz) δ: 9.80 (1H, s), 9.36 (1H, d), 9.30 (1H, d), 8.58 (1H, t), 8.21 (2H, d), 8.12 (2H, d), 7.95 (1H, t), 7.85-7.80 (3 H, m), 7.68 (2H, t), 6.71 (2H, s), 4.95-4.93 (2H, m), 4.82-4.80 (2H, m). Mass (m/z): 390, 391, 392.

EXAMPLE 30 1-(2-Thien-2′-yl-2-oxoethyl)-3-(phenylcarbonyl hydrazino carbonyl) pyridinium bromide (compound 29)

[0221] Yield: 45% m.p.: 80-81° C. IR(KBr Cm⁻¹): 1700, 1663, 1631 ¹HNMR (DMSOd₆, 400 MHz) δ: 11.49 (1H, s), 10.95 (1H, s), 9.67 (1H, s), 9.34 (1H, d), 9.27 (1H, d), 8.52-8.48 (1H, m), 8.29-8.28 (2H, m), 8.00 (2H, d), 7.68 (1H, t), 7.59 (2H, t), 7.46 (1H, t), 6.63 (2H,s) Mass (m/z): 366, 367, 368, 369

EXAMPLE 31 1-(2-Ethoxy-2-oxoethyl -3-((phenylmethyl)sulfonyl hydrazino carbonyl) pyridinium bromide (compound 30)

[0222] Yield: 50% m.p.: 147-148° C. IR (KBr, cm⁻¹): 1749, 1698, 1640 ¹HNMR (DMSOd₆, 400 MHz) δ: 11.57 (1H, s), 10.21 (1H,s), 9.75 (1H,s), 9.38 (1H, d), 9.24 (1H, d), 8.59-8.56(1H, m), 7.67-7.65 (2H, m), 7.58-7.52 (3H, m), 5.90(2H, s), 4.68 (2H, s), 4.45-4.39(2H, q), 1.43 (3H, t). Mass (m/z): 377, 378, 379

EXAMPLE 32 1-(2-Phenyl-2-oxoethyl)-3-((phenylmethyl)sulfonyl hydrazino carbonyl)pyridinium bromide (compound 31)

[0223] Yield: 80% m.p.: 205-207° C. IR (KBr, Cm⁻¹): 1687, 1637 ¹HNMR (DMSOd₆, 400 MHz) δ: 11.59 (1H,s), 10.20 (1H,s), 9.71 (1H,s), 9.33 (1H, d), 9.27 (1H, d), 8.62-8.59(1H, m), 8.25-8.23 (2H, d), 7.99-7.95 (1H, t), 7.86-7.82 (2H, t), 7.67-7.65 (2H, m), 7.57-7.52 (3H, m), 6.72 (2H, s), 4.69 (2H, s). Mass (m/z): 410, 411, 412, 413

EXAMPLE 33 N,N′-Bis [3-carbonyl-1-(2-furan-2′-yl-2-oxoethyl) pyridinium]hydrazine dibromide. (Compound No: 32)

[0224] Yield: 23% m.p.: 267-269° C. (dec) IR (KBr, cm⁻¹): 1687, 1660 ¹H NMR (DMSO d₆, 400 MHz) δ: 11.65 (2H,s), 9.56 (2H,s), 9.21-9.15 (4H,m), 8.48-8.44 (2H,t), 8.23 (2H,s), 7.74-7.73 (2H,d), 6.91-6.90 (2H,d) 6.34 (4H,s) Mass (m/z): 459, 460, 461

EXAMPLE 34 N,N′-Bis [3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl) pyridinium]hydrazine dichloride. (Compound No: 33)

[0225] Yield: 35% m.p.: 275-277° C. IR (KBr, cm⁻¹): 3374, 1665,1632, 1410 ¹H NMR (DMSO d₆, 400 MHz) δ: 11.88 (2H,s), 9.66 (2H,s), 9.29-9.24 (4H,m), 8.48-8.44 (2H,m), 8.25-8.23 (4H,m), 7.43-7.41 (2H,m), 6.53 (4H,s). Mass (m/z): 491, 492, 493, 494

EXAMPLE 35 1-(2-Thien-2′-yl-2-oxoethyl)-3-((2-(1-oxo-3-cyclohexyl)-propyl)-hydrazino carbonyl)-pyridinium bromide(Compound No: 34)

[0226] Yield: 15% m.p.: 217-219° C.(dec) IR (KBr, cm⁻¹): 3190, 1708, 1667 and 1404 ¹H NMR (DMSO d₆, 400 MHz) δ: 11.07 (1H,s), 10.22 (1H,s), 9.51 (1H,s), 9.16-9.15 (1H,d), 9.06-9.04 (1H,d), 8.42-8.40 (1H,m), 8.25-8.21 (2H,m), 7.43-7.40 (1H,m), 6.44 (2H,s), 2.25-2.22 (2H,t), 1.72-1,.60 (5H,m), 1.49-1.43 (2H,q), 1.24-1.10 (4H,m), 0.9-0.85 (2H,m) Mass (m/z): 400, 401, 402 and 403

EXAMPLE 36 1-(2-Phenylamino-2-oxo ethyl)-3-({2-(1-oxo -3-cyclohexyl)-propyl}-hydrazino-carbonyl}-pyridinium bromide. (Compound No: 35);

[0227] Yield: 25% m.p.: 234-236° C. (dec) IR (KBr, cm⁻¹): 1689, 1652 and 1625 ¹H NMR (DMSO d₆, 400 MHz) 67 : 11.11 (1H,s), 10.95 (1H,s), 10.23 (1H,s), 9.56 (1H,s), 9.23-9.21 (1H,d), 9.06-9.04 (1H,d), 8.38-8.35 (1H,m), 7.62-7.60 (2H,d), 7.37-7.33 (2H,t), 7.12-7.09 (1H,t), 5.75 (2H,s), 2.25-2.22 (2H,t), 1.72-1.60 (5H,m) 1.49-1.43 (2H,m), 1.25-1.10 (4H,m), 0.91-0.83 (2H,m) Mass (m/z): 409, 410, 411 and 412

EXAMPLE 37 1-(2-Thien-2′-yl-2-oxoethyl)-3-[2-(benzoyloxy)ethylamino carbonyl]-pyridinium bromide (Compound No: 36)

[0228] Yield: 40% m.p.: 125-127° C. IR (KBr, cm⁻¹): 1710 and 1675 ¹H NMR (DMSO d₆, 400 MHz) δ: 9.48 (1H,s), 9.43-9.41 (1H,t), 9.12-9.11 (1H,d), 9.05-9.02 (1H,d), 8.40-8.36 (1H,m), 8.25-8.20 (2H,m), 8.00-7.98 (2H,m), 7.68-7.64 (1H,m), 7.54-7.50 (2H,m), 7.42-7.40 (1H,m), 6.43 (2H,s), 4.46-4.43 (2H,t), 3.77-3.73 (2H,q) Mass (m/z): 395, 396, 397 and 398

EXAMPLE 38 1-(4-Ethoxy-2,4-dioxobutyl)-3-(2-(benzoxyloxy)ethylamino carbonyl)-pyridinium chloride. (Compound No: 37)

[0229] Yield: 35% m.p.: 147-149° C. IR (KBr, cm⁻¹): 1743, 1720, 1680 and 1627 ¹H NMR (DMSO d₆, 400 MHz) δ: 9.62-9.59 (1H,t), 9.32-9.29 (1H,s), 9.05-9.03 (1H,d), 8.93-8.90 (1H,d), 8.27-8.24 (1H,m), 7.92-7.89 (2H,d), 7.59-7.55 (1H,m), 7.45-7.41 (2H,m), 5.82 (2H,s), 4.37-4.34 (2H,t), 4.08-4.03 (2H,q), 3.80 (2H,s), 3.67-3.63 (2H,q), 1.15-1.11 (3H,t), Mass (m/z): 399, 400 and 401

EXAMPLE 39 1-(2′,4′-Dichlorophenyl-2-oxoethyl)-3-(2-methoxyethyl aminocarbonyl)-pyridinium bromide. (Compound No: 38)

[0230] Yield: 70% m.p.: 93-95° C. IR (KBr, cm⁻¹): 1704, 1664 and 1636 ¹H NMR (DMSO ₆, 400 MHz) δ: 9.48 (1H,s), 9.29 (1H,bs), 9.11-9.08 (2H,m), 8.41-8.38 (1H,m), 8.15-8.13 (1H,d), 7.92-7.91 (1H,t), 7.78-7.75 (1H,m), 6.44 (2H,s) 3.52 (2H,bs), 3.51 (2H,bs), 3.28 (3H,s) Mass (m/z): 367, 368, 369 and 370

EXAMPLE 40 N,N′-Bis-[3-carbonyl-1-(2-cyclopropylamino-2-oxoethyl) pyridinium] hydrazine dichloride. (Compound No: 39)

[0231] Yield: 40% m.p. .228-230° C. IR (KBr cm⁻¹): 1675, 1636 and 1298 ¹H NMR (DMSO d₆, 400 MHz) δ: 11.85 (2H,s), 9.59 (2H,s), 9.25-9.19 (4H,m), 9.00-8.99 (2H,d), 8.39-8.36 (2H,m), 5.53 (4H,s), 2.73-2.66 (2H,m), 0.78-0.62 (4H,m), 0.53-0.49 (4H,m) Mass (m/z) 437, 438 and 439

EXAMPLE 41 1-(2-Cyclopropylamino-2-oxoethyl)-3-(2-methoxyethylaminocarbonyl)-pyridinium chloride. (Compound No: 40)

[0232] Yield: 10% m.p.: 122-124° C. IR (KBr, cm⁻¹): 1661, 1633, 1549 and 1121 ¹H NMR (DMSO d₆, 400 MHz) δ: 9.40 (1H,s), 9.08-9.02 (2H,m), 8.28-8.25 (1H,m), 5.53 (2H,s), 3.66-3.61 (4H,m), 3.39 (3H,s), 2.78-2.74 (1H,m), 0.80-0.75 (2H,m), 0.64-0.61 (2H,m) Mass (m/z): 278, 279 and 280

EXAMPLE 42 N,N′-Bis [3-carbonyl-1-(2-isopropylamino-2-oxoethyl) pyridinium]hydrazine dichloride. (Compound No: 41)

[0233] Yield: 35% m.p.: 114-116° C. (dec) IR (KBr, cm⁻¹): 1707, 1668 and 1637 ¹H NMR (DMSO d₆, 400 MHz) δ: 11.84 (2H,s), 9.59 (2H,s), 9.21-9.18 (4H,m), 8.74-8.72 (2H,d), 8.39-8.35 (2H,m), 5.53 (4H,s), 3.92-3.84 (2H,m), 1.14-1.02 (12H,d) Mass (m/z): 441, 442 and 443

EXAMPLE 43 1-(2-Thien-2′yl-2-oxoethyl)-3-(2-(2-chloro-3-pyridoylhydrazinocarbonyl)-pyridinium chloride. (Compound No: 42)

[0234] Yield: 56% m.p.: 233-235° C. IR (KBr, cm⁻¹): 1680, 1637, 1404 and 1293 ¹H NMR (DMSO d₆, 400 MHz) δ: 11.62 (1H,s), 11.05 (1H,s), 9.62 (1H,s), 9.24-9.23 (1H,d), 9.18-9.16 (1H,d), 8.58-8.56 (1H,m), 8.46-8.43 (1H,m), 8.26-8.24 (2H,m), 8.02-8.00 (1H,m), 7.61-7.58 (1H,m), 7.43-7.41 (1H,m), 6.51 (2H,s) Mass (m/z): 401, 402, 403, 404 and 405

EXAMPLE 44 1-(2-Isopropylamino-2-oxoethyl)-3-(2-methylsulfonylhydrazinocarbonyl)-pyridinium chloride. (Compound No: 43)

[0235] Yield: 10% m.p.: 227-229° C. IR (KBr, cm⁻¹): 1691, 1670, 1566 and 1330 ¹H NMR (DMSO d₆, 400 MHz) 67 : 11.55 (1H,s), 9.94 (1H,s), 9.52 (1H,s), 9.16-9.14 (1H,m), 9.09-9.07 (1H,m), 8.72-8.70 (1H,m), 8.34-8.30 (1H,m), 5.50 (2H,s), 3.89-3.84 (1H,m), 3.11 (3H,s), 1.13-1.12 (6H,d) Mass (m/z): 315, 316 and 317

EXAMPLE 45 1-(2-(1-Pyrrolidinyl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride (Compound No: 44)

[0236] Yield: 21.00% m.p.: 205-207° C. IR (KBr, cm⁻¹): 1699, 1646 and 1589 ¹HNMR: (DMSO d₆, 400 MHz) 67 : 11.50 (1H, s), 9.94 (1H, s), 9.46 (1H, s), 9.11-9.06 (2H, m), 8.36-8.33 (1H, t), 5.75 (2H, s), 3.55-3.48 (3H, m), 3.10 (3H, s), 2.00-1.95 (2H, m), 1.87-1.81 (2H, m) Mass (m/z): 327, 328, 329 and 330

EXAMPLE 46 1-(2-Thien-2′-yl-2-oxoethyl-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride (Compound No: 45)

[0237] Yield: 31.00% m.p.: 215-217° C. IR (KBr, cm⁻¹): 1685, 1666 and 1635 ¹HNMR: (DMSO d₆, 400 MHz) 67 : 11.49, (1H, s), 9.96 (1H, s), 9.55 (1H, s), 9.18 (1H, d), 9.10 (1H, d), 8.43-8.39 (1H, t), 8.25-8.22 (2H, m), 7.42 (1H, t) 6.47 (2H, s), 3.09 (3H, s). Mass (m/z): 340, 341, 342 and 343

EXAMPLE 47 N,N′-Bis[3-carbonyl-1-(2-hydroxy-2-oxoethyl) pyridinium]hydrazine dichloride (Compound No: 46)

[0238] Yield: 43.00% m.p.: 235-240° C. (d) IR (KBr, cm⁻¹): 1743, 1700 and 1672 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.89 (2H, s), 9.69 (2H, s), 9.31-9.29 (2 H, d), 9.25-9.23 (2H, d), 8.43-8.39 (2H, t) 5.70 (4H, s) Mass (m/z): 360, 361, 362

EXAMPLE 48 1-(2-Thien-2′-yl-2-oxoethyl)-3-((2-methoxy ethyl) amino carbonyl) -5-bromo pyridinium chloride (Compound No: 47)

[0239] Yield: 31.00% m.p.: 180-182° C. IR (KBr, cm⁻¹): 1661 and 1620 ¹HNMR (DMSO d₆, 400 MHz) δ: 9.58-9.54 (2H, d), 9.43-9.39 (2H, d), 8.25-8.21 (2H, m), 7.41 (1H, t), 6.43 (2H, s), 3.51 (4H, m), 3.29 (3H, s). Mass (m/z): 384, 385, 386, 387 and 388

EXAMPLE 49 1-(2-Thien-2′-yl-2-oxoethyl)-3-[1-oxo-1-(2-methoxycarbonyl) pyridyl] hydrazino pyridinium chloride (Compound No: 48)

[0240] Yield: 30.00% m.p.: 222-225° C. IR (KBr, cm⁻¹): 1726, 1708 and 1662 ¹H NMR (DMSO d₆, 400 MHz) δ: 11.47 (1H, s), 11.23 (1H, s), 9.58 (1H, s), 9.22-9.15 (3H, m), 8.56-8.53 (1H, d), 8.46-8.43 (1H, t) 8.25-8.21 (3H, m), 7.42 (1H, t), 6.49 (2H, s), 3.95 (3H, s) Mass (m/z): 425, 426 and 427

EXAMPLE 50 1-[1-(2-Thien-2′-yl-2-oxoethyl)-6methyl-3-carbonyl pyridinium]-2-[1-(2-Thien-2′-yl-2-oxoethyl)-3—carbonyl pyridinium] hydrazine dichloride(compound no: 49)

[0241] Yield: 40% M.P.: 76-80° C. (dec) IR (KBr,cm⁻¹): 1637, 1513 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.69(2H,s), 9.59-9.53(2H,d), 9.19(2H,m), 9.05(1H,d), 8.46-8.43(1H,t), 8.34(1H,d), 8.27-8.23(4H,m), 7.45-7.41(2H,m), 6.56(2H,s), 6.48(2H,s), 2.81 (3H,s). Mass (m/z): 505, 506, 507.

EXAMPLE 51 1(2-Thien-2′-yl-2-oxoethyl)-3-(isopropylsulfonyl hydrazino carbonyl) pyridinium bromide(compound no: 50)

[0242] Yield: 70% M.P: 90-95° C. (dec) IR (KBr,cm⁻¹) 1638, 1589 ¹NMR (DMSO d₆, 400 MHz) δ: 11.27(1H,s), 9.91(1H,s), 9.60(1H,s), 9.19-9.15(2H,m), 8.42-8.36(1H,m), 8.25-8.21(2H,m), 7.43-7.41(1H,t), 6.45(2H,s), 1.35-1.34(6H,d). Mass (m/z): 368, 369, 370

EXAMPLE 52 1-(2-(4-Benzyl piperidin-1-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride(compound no: 51)

[0243] Yield: 17% M.P: 76-78° C. IR (KBr,cm⁻¹): 1684, 1650, 1556, 1540. ¹HNMR (DMSO d₆, 400 MHz) δ: 11.46(1H,s), 9.55(1H,s), 9.46(1H,s), 9.09-9.03(2H,m), 8.36-8.32(1H,t), 7.33-7.29(2H,m), 7.23-7.19(3H,m), 5.88-5.79(2H,m), 4.30-4.27(1H,d), 3.76-3.73(1H,d), 3.10(4H,m), 2.64(1H,t), 2.57-2.55(2H,d), 1.85(1H,bs), 1.72-1.63(2H,t), 1.36-1.28(1H,q), 1.13-1.03(1H,m) Mass (m/z): 431, 432, 433

EXAMPLE 53 1-(2-(2-Ethoxy carbonyl pyrrolidin-1-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride. (compound no: 52)

[0244] Yield: 14% M.P: 88-91° C. IR (KBr,cm⁻¹): 1735, 1665, 1539 ¹HNMR (DMSO d₆, 400 MHz) 67 : 11.48(1H,s), 9.96(1H,s), 9.46(1H,s), 9.09-9.05(2H,m), 8.38-8.34(1H,t), 5.94-5.80(2H,q), 4.37-4.36(1H,d), 4.08-4.06(2H,d), 3.68-3.65(2H,m), 3.09(4H,m), 2.23-2.18(2H,m), 2.04-1.93(3H,m), 1.18-1.09(3H,t) Mass (m/z): 399, 400, 401

EXAMPLE 54 1-(2-Thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl)-5-bromo pyridinium bromide. (compound no: 53)

[0245] Yield: 54% M.P: Above 190-195° C. (dec) IR (KBr,cm⁻¹): 1682, 1557, 1540, 1520 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.35(1H,s), 10.01(1H,s), 9.57-9.54(2H,d), 9.32(1H,s), 8.26-8.22(2H,m), 7.42(1H,s), 6.39(2H,s), 3.08(3H,s) Mass (m/z): 418, 419, 420

EXAMPLE 55 1-(2-Thien-2′-yl-2-oxoethyl)-3-(ethoxycarbonyl hydrazino carbonyl) pyridinium bromide. (compound no: 54)

[0246] Yield: 69% M.P: 155-157° C. IR (KBr,cm⁻¹): 1731, 1665, 1637 ¹H NMR (DMSO d₆, 400 Mz) δ: 11.04(1H,s), 9.59(1H,s), 9.53(1H,s), 9.18(1H,s), 9.05-9.04(1H,d), 8.42(1H,s), 8.25-8.23(2H,m), 7.43(1H,s), 6.46(2H,s), 4.12-4.11(2H,s), 1.23(3H,s) Mass (m/z): 334, 335, 336

EXAMPLE 56 1-(2-(5-chloro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide (compound no: 55)

[0247] Yield: 87% M.P: 228-230° C. IR (KBr,cm⁻¹): 1708, 1664, 1631, 1550 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.40(1H,s), 9.98(1H,s), 9.50(1H,s), 9.15(1H,d), 9.061H,d), 8.43-8.39(1H,t), 8.16-8.15(1H,d), 7.51-7.50(1H,d), 6.41(2H,s), 3.09 (3H,s) Mass (m/z): 374, 375, 376, 377

EXAMPLE 57 N,N′-Bis[3-carbonyl-1-(2-(4-nitro-thien-2-yl)-2-oxoethyl)pyridinium] hydrazine dichloride. (compound no: 56)

[0248] Yield: 27% M.P: 204-207° C. IR (KBr,cm⁻¹): 1681, 1539, 1514 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.90(2H,s), 9.63(2H,s), 9.31-9.30(4H,m), 9.24-9.22(2H,m), 8.87(2H,s), 8.49-8.46(2H,t), 6.56 (4H,s) Mass (m/z): 581, 582, 583

EXAMPLE 58 1-(2-Thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) -6-methyl pyridinium bromide. (compound no: 57)

[0249] Yield: 14% M.P: 90-95° C.(dec) IR (KBr,cm⁻¹): 1677, 1575 ¹HNMR (DMSO ₆, 400 MHz) δ: 11.32(1H,s), 9.97(1H,s) 9.52(1H,s), 8.94-8.92(1H,d), 8.32-8.24(3H,m), 7.44(1H,t), 6.54(2H,s), 3.08(3H,s), 2.79(3H,s) Mass (m/z): 354, 355, 356

EXAMPLE 59 N,N′-Bis[3-carbonyl-1-(2-(5-methyl-thien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride. (compound no: 58)

[0250] Yield: 37% M.P: Above 166-168° C.(dec) IR (KBr,cm⁻¹): 1666, 1500 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.73(2H,s), 9.59(2H,s), 9.19-9.15(4H,d) 8.45-8.42(2H,t), 8.06-8.05(2H,d), 7.15-7.14(2H,d), 6.43 (4H,s), 2.59(6H,s) Mass (m/z): 519, 520, 521, 522

EXAMPLE 60 N,N′-Bis[3-carbonyl-1-(2-(2-ethoxycarbonyl pyrrolidin-1-yl) -2-oxoethyl) pyridinium] hydrazine dichloride. (compound no: 59)

[0251] Yield: 28% M.P: 118-120° C. IR (KBr,cm⁻¹): 1660, 1510 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.75(2H,s), 9.51(2H,s), 9.20-9.10(4H,m) 8.43-8.40(2H,t), 5.97-5.83(4H,m), 4.39-4.36(2H,m), 4.27-4.22(1H,q), 4.12-4.05(4H,m), 3.71-3.63(4H,m), 3.48-3.40(1H,m), 2.26-2.19(2H,m), 2.05-1.91(5H,m), 1.30-1.27(1H,t), 1.19-1.15(5H,t) Mass (m/z): 609, 610, 611

EXAMPLE 61 1-[1-(2-Thien-2′-yl-2-oxoethyl)-5-aminocarbonyl-3-carbonyl pyridinium]-2-[1-(2-Thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium] hydrazine dichloride (compound no: 60)

[0252] Yield: 54% M.P: Above 127-129° C.(dec) IR (KBr,cm⁻¹): 1678, 1513 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.86(2H,s), 9.83-9.64(4H,t), 9.24-9.23(2H,s), 8.82(1H,s), 8.48-8.45(1H,t), 8.34(1H,s) 8.26-8.24(4H,m), 7.44-7.42(2H,d), 6.52-6.46(4H,d) Mass (m/z): 534, 535, 536

EXAMPLE 62 1-(2-(4-carbethoxy-thiazolidin-3yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride (compound no: 61)

[0253] Yield: 29% M.P: 190-192° C. IR (KBr,cm⁻¹): 1673, 1541 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.50(1H,s), 9.55(1H,s), 9.48(1H,s), 9.12-9.08(2H,m), 8.39-8.34(1H,t), 6.04-5.99(2H,m), 4.94-4.91(1H,m), 4.87-4.84(1H,d), 4.73-4.71(1H,d), 4.28-4.23(1H,q), 4.14-4.09(1H,q), 3.43-3.38(1H,m), 3.27-3.22(1H,m), 3.10(3H,s), 1.30-1.27(1H,t), 1.20-1.17(2H,m) Mass (m/z): 439, 440, 441

EXAMPLE 63 N,N′-Bis[3-carbonyl-1-(2-(5-chloro-thien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride. (compound no: 62)

[0254] Yield: 35% M.P: Above 200-205° C. (dec) IR (KBr,cm⁻¹): 1674, 1590, 1500 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.90(2H,s), 9.64-9.61(2H,d), 9.29-9.20(4H,m), 8.47-8.44(2H,t), 8.18-8.17(2H,d), 7.51-7.50(2H,d), 6.49-6.48(4H,s) Mass (m/z): 559, 560, 561, 562, 563, 564

EXAMPLE 64 1-(2-(5-Methyl-thien-2-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride (compound no: 63)

[0255] Yield: 22% M.P.: 196-198° C. IR (KBr,cm⁻¹): 1689, 1657 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.47(1H,s), 9.98(1H,s), 9.53(1H,s), 9.17-9.16(1H,d), 9.09-9.07(1H,d), 8.42-8.38(1H,t), 8.06-8.05(1H,d), 7.15-7.14(1H,d), 6.41(2H,s), 3.09(3H,s), 2.59(3H,s) Mass (m/z): 354, 355, 356, 357

EXAMPLE 65 1-(2-(4-Nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide. (compound no: 64)

[0256] Yield 52% M.P: Above 200-205° C.(dec) IR (KBr,cm): 1688, 1631, 1541 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.41(1H,s), 9.50(1H,s) 9.309-9.306(1H,d), 9.17-9.15(1H,d), 9.09-9.07(1H,d), 8.866-8.862(1H,d), 8.45-8.41 (1H,t), 6.50(2H,s), 3.09(3H,s) Mass (m/z): 385, 386, 387

EXAMPLE 66 1-(2-Phenylamino-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium chloride (compound no: 65)

[0257] Yield: 45% M.P: 165-167° C. IR (KBr,cm⁻¹): 1679, 1626, 1600, 1497 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.18(1H,s), 11.10(1H,s), 9.62(1Hs), 9.24-9.22(1H,d), 9.17-9.15(1H,d), 8.40-8.36(1H,t), 8.19(1H,s), 7.63-7.61(2H,d), 7.37-7.33(2H,t), 7.20-7.16(2H,t), 7.12-7.09(1H,t), 6.88-6.86(2H,d), 6.78-6.74(1H,t), 5.78(2H,s) Mass (m/z): 347, 348, 349

EXAMPLE 67 1-(2-Phenylamino-2-oxoethyl)-4-[2-(benzoyloxy) ethylamino carbonyl] pyridinium chloride (compound no: 66)

[0258] Yield 40% M.P: 178-180° C. IR (KBr,cm⁻¹): 1700, 1666, 1559 ¹HNMR (DMSO ₆, 400 MHz) δ: 11.13(1H,s), 9.74-9.71(1H,t), 9.23-9.22(2H,d), 8.52-8.50(2H,d), 8.01-7.99(2H,d), 7.68-7.60(3H,m), 7.54-7.51(2H,t), 7.36-7.32(2H,t), 7.12-7.08 (1H,t), 5.75 (2H,s), 4.47-4.45(2H,t), 3.77-3.72(2H,q).

[0259] Mass (m/z): 404, 405, 406

EXAMPLE 68 1-2-(5-Nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride (compound no: 67)

[0260] Yield: 10% M.P: Above 105-110° C.(dec) IR (KBr,cm⁻¹) 1680, 1620 ¹H NMR (DMSO d₆, 400 MHz) δ: 11.48(1H,s), 9.98(1H,s), 9.52(1H,s), 9.16-9.10(2H,m), 8.45-8.41(1H,t), 8.35-8.34(1H,d), 8.25-8.24(1H,d), 6.50(2H,s), 3.09(3H,s). Mass (m/z): 385, 386, 387

EXAMPLE 69 1-(2-Thien-2′-yl-2-oxoethyl)3-(Trifluromethanesulfonyl hydrazino carbonyl)-pyridinium bromide (compound no: 68)

[0261] Yield: 22% M.P: 77-79° C. IR KBr,cm⁻¹): 2960, 1690, 1673, 1591, ¹HNMR (DMSO d₆, 400 MHz) δ: 11.76(1H,s), 11.27(1H,s), 9.61(1H,s), 9.20-9.19(1H,d), 9.07-9.05(1H,d), 8.44-8.41(1H,t), 8.25-8.22(2H,m), 7.34-7.41 (1H,m), 6.46 (2H,s). Mass (m/z): 394, 395, 396

EXAMPLE 70 1-(2-Thien-2′-yl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide (compound no. 69)

[0262] Yield: 10% M.P: 192-194° C. IR (KBr,cm⁻¹): 1669, 1663, 1603, ¹HNMR (DMSO d₆, 400 MHz) δ: 10.99(1H,s), 9.54(1H,s), 9.17-9.14(2H,t), 8.44-8.41(1H,t), 8.25-8.22(3H,m), 7.43-7.41(1H,t), 7.20-7.16(2H,t), 6.87-6.85(2H,d), 6.79-6.75(1H,t), 6.46(2H,s) Mass (m/z): 338, 339, 340

EXAMPLE 71 1-(2-Thien-2′-yl-2-oxoethyl)-3-(p-methoxy phenyl sulfonyl hydrazino carbonyl) pyridinium bromide (compound no. 69)

[0263] Yield: 28% M.P: 126-128° C. IR (KBr,cm⁻¹): 1672, 1653, 1596 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.34-11.33(1H,d), 10.27-10.26(1H,d), 9.34(1H,s), 9.13-9.12(1H,d), 8.94-8.92(1H,d), 8.38-8.34(1H,t), 8.24-8.19(2H,m), 7.82-7.75(2H,m), 7.42-7.40(1H,t), 7.07-7.04(2H,d), 6.40(2H,s), 3.81(3H,s). Mass (m/z): 432, 433, 434

EXAMPLE 72 1-(2-Ethoxy-2-oxoethyl)-3-(phenyl aminocarbonyl hydrazino carbonyl) pyridinium bromide. (compound no. 71)

[0264] Yield: 25% M.P: 183-185° C. IR (KBr,cm⁻¹): 1746, 1717, 1682 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.02(1H,s), 9.57(1H,s), 9.22-9.21(1H,d), 9.11-9.09(1H,d), 9.00(1H,s), 8.57(1H,s), 8.44-8.41(1H,m), 7.47-7.45(2H,d), 7.29-7.25(2H,t), 7.00-6.96(1H,t), 5.74(2H,s), 4.28-4.23(2H,q), 1.28-1.25(3H,t). Mass (m/z): 343, 344, 345, 346

EXAMPLE 73 1-(2-Ethoxy-2-oxoethyl)-3-(p-toluene sulfonyl hydrazino carbonyl) Pyridinium bromide. (compound no. 72)

[0265] Yield: 54% M.P: 174-176° C. IR (KBr,cm⁻¹): 1746, 1712, 1634 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.33(1H,s), 10.36(1H,s), 9.37(1H,s), 9.18-9.16(1H,d), 8.93-8.91(1H,d), 8.37-8.33(1H,t), 7.78-7.76(2H,d), 7.37-7.35(2H,d), 5.68 (2H,s), 4.26-4.20(2H,q), 2.37(3H,s), 1.27-1.23(3H,t). Mass (m/z): 378, 379, 380, 381

EXAMPLE 74 1-(2-Phenyl-2-oxoethyl)-3-(phenylamino carbonyl hydrazino carbonyl) pyridinium bromide. (compound no. 73)

[0266] Yield: 70% M.P: 206-208° C. IR (KBr,cm⁻¹): 1713, 1684, 1634 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.05(1H,s), 9.55(1H,s), 9.18-9.13(2H,m), 9.02(1H,s), 8.59(1H,s), 8.49-8.45(1H,m), 8.09-8.07(2H,d), 7.84-7.80(1H,t), 7.71-7.67(2H,t), 7.49-7.47(2H,d), 7.30-7.26(2H,t), 7.01-6.97 (1H,t), 6.56(2H,s). Mass (m/z): 375, 376, 377

EXAMPLE 75 1-(2-Phenylamino-2-oxoethyl)-3-(benzyl sulfonyl hydrazino carbonyl) pyridiniumchloride. (compound no. 74)

[0267] Yield: 48% M.P: 208-210° C. IR (KBr,cm⁻¹): 1712, 1681, 1632 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.46(1H,s), 10.80(1H,s), 9.59(1H,s), 9.22-9.20(1H,d), 9.08-9.06(1H,d), 8.38-8.36(1H,t), 7.60-7.58(2H,d), 7.49(2H,m), 7.39-7.34(5H,m), 7.13-7.10(1H,t), 5.74(2H,s), 4.52(2H,s). Mass (m/z): 425, 426, 427, 428

EXAMPLE 76 1-(2-Phenyl-2-oxoethyl)-4-(methanesulfonyl hydrazino carbonyl) pyridinium bromide (compound no. 75)

[0268] Yield: 10% M.P: 190-192° C. IR (KBr,cm⁻¹): 1679, 1630, 1650 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.54(1H,s), 10.03(1H,s), 9.20-9.18(2H,d), 8.59-8.57(2H,d), 8.10-8.08(2H,d), 7.84-7.80(1H,t), 7.71-7.67(2H,t), 6.56(2H,s), 3.08(3H,s). Mass (m/z): 334, 335, 336

EXAMPLE 77 1-(2-Phenyl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide (compound no. 76)

[0269] Yield: 36% M.P: 204-206° C. IR (KBr,cm⁻¹): 1686, 1653, 1630 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.01(1H,s), 9.53(1H,s), 9.17-9.16(2H,m), 8.46-8.42(1H,t), 8.09-8.07(2H,d), 7.82-7.78(1H,t), 7.69-7.65(2H,t), 7.20-7.16(2H,t), 6.88-6.86(2H,d), 6.79-6.75(1H,t), 6.56(2H,s) Mass (m/z): 332, 333

EXAMPLE 78 1-(2-Ethoxy-2-oxoethyl)-4[-2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide (compound no. 77)

[0270] Yield: 82% M.P: 154-156° C. IR (KBr,cm⁻¹): 1742, 1719, 1707, 1675 ¹HNMR (DMSO d₆, 400 MHz) δ: 9.57-9.54(1H,t), 9.22-9.20(2H,d), 8.51-8.49(2H,d), 8.00-7.98(2H,d), 7.68-7.64(1H,t), 7.54-7.51(2H,t), 5.72(2H,s), 4.47-4.44(2H,t), 4.27-4.21(2H,q), 3.76-3.72(2H,q), 1.27-1.24. (3H,t) Mass (m/z): 357, 358, 359.

EXAMPLE 79 1-(2-Ethoxy-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide.(compound no. 78)

[0271] Yield: 37% M.P: 185-187° C. IR (KBr,cm⁻¹): 1740, 1690, 1630. ¹HNMR (DMSO d₆, 400 MHz) δ: 11.01(1H,s), 9.58(1H,s), 9.23-9.14(2H,m), 8.42-8.39(1H,t), 8.19(1H,s), 7.20-7.16(2H,t), 6.87-6.85(2H,d), 6.78-6.75(1H,t), 5.75(2H,s), 4.28-4.22(2H,q), 1.28-1.24(3H,t) Mass (m/z): 300, 301, 302.

EXAMPLE 80 1-(2-Phenyl-2-oxoethyl)-3-(p-methoxyphenyl sulfonyl hydrazino carbonyl) pyridinium bromide (compound no. 79)

[0272] Yield: 59% M.P: 188-190° C. IR (KBr,cm⁻¹) 1671, 1634, 1580. ¹HNMR (DMSO d₆, 400 MHz) δ: 11.26-11.25(1H,d), 10.17-10.16(1H,d), 9.24(1H,s), 9.03-9.01(1H,d), 8.87-8.85(1H,d), 8.31-8.27(1H,t), 7.97-7.96(2H,d), 7.74-7.69(3H,m), 7.60-7.56(2H,t) 6.99-6.97(2H,d), 6.40(2H,s), 3.73(3H,s). Mass (m/z): 426, 427, 428, 429

EXAMPLE 81 1-(2-Phenyl-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide (compound no. 80)

[0273] Yield: 92% M.P: 202-204° C. IR (KBr,cm⁻¹): 1715, 1692, 1650 ¹HNMR (DMSO d₆, 400 MHz) δ: 9.55(1H,s), 9.14-9.13(2H,d), 8.52-8.51(2H,d), 8.07-7.99(4H,m), 7.80-7.51(6H,m), 6.52(2H,s), 4.46(2H,s), 3.76-3.75(2H,s). Mass (m/z): 389, 390, 391, 392

EXAMPLE 82 1-(2-Ethoxy-2-oxoethyl)-4-(p-methanesulfonyl hydrazino carbonyl) pyridinium bromide. (compound no. 81)

[0274] Yield: 45% M.P: 94-96° C. IR (KBr,cm⁻¹): 1726, 1681, 1643 ¹HNMR (DMSO d₆, 400 MHz) δ: 11.49(1H,s), 9.98(1H,s), 9.23-9.21(2H,d), 8.54-8.52(2H,d), 5.73(2H,s), 4.28-4.22(2H,q), 3.09(3H,s), 1.28-1.25(3H,t). Mass (m/z): 302, 303, 304, 305.

[0275] Pharmaceutical Compositions

[0276] Pharmaceutical compositions may be prepared with a pharmaceutically effective quantity of compounds of general formula I, individually or in combination. The following pharmaceutical formulations suggested are by way of example alone and in no way restrict the forms in which they can be used.

[0277] Oral Formulations

[0278] Oral formulations may be administered as solid dosage forms for example pellets, powders, sachets or discreet units such as tablets or capsules and like. Other orally administered pharmaceutical preparations include monophasic and biphasic liquid dosage forms either in ready to use form or forms suitable for reconstitution such as mixtures, syrups, suspensions or emulsions. The preparations in addition may contain diluents, dispersing agents, buffers, stabilizers, solubilizers, surfactants, preservatives, chelating agents and/or other pharmaceutical additives as are used. Aqueous or non aqueous vehicle or their combination may be used and if desired may contain suitable sweetener, flavoring agent or similar substances. In case of suspension or emulsion a suitable thickening agent or suspending agent or emulsifying agent may be present in addition. Alternatively, the compounds may be administered as such in their pure form unassociated with other additives for example as capsules or sachets. It may also be administered with a vehicle. Pharmaceutical preparations can have a slow, delayed or controlled release of active ingredients as is provided by a matrix or diffusion controlled system.

[0279] When the present invention or its salts or suitable complexes is presented as a discreet unit dosage form like tablet, it may contain in addition medically inert excipients as are used in the art. Diluents such as starch, lactose, dicalcium phosphate, talc, magnesium stearate, polymeric substances like methyl cellulose, fatty acids and derivatives, sodium starch glycollate, etc. may also be used.

EXAMPLE 83 Preparation of Oral Dosage Form

[0280] A typical tablet has the following composition: Active ingredient of formula I as given above Lactose 135 mg  Starch 76 mg Polyvinyl pyrolidone (K-30)  2 mg Talc 1.5 mg  Magnesium Stearate 1.0 mg 

[0281] Parenteral Formulations

[0282] For parenteral administration, the compounds or their salts or suitable complexes thereof may be present in a sterile vehicle which may be an aqueous or non aqueous vehicle or a combination thereof. The examples of vehicles are water, ethyl oleate, oils and derivatives of polyols, glycols and their derivatives. It may contain additives common in injectable preparations like stabilizers, solubilizers, pH modifiers, buffers, antioxidants, cosolvents, complexing agents, tonicity modifiers, etc.

[0283] Some suitable additives are for example tartrate, citrate or similar buffers, alcohol, sodium chloride, dextrose and high molecular weight polymers. Another alternative is sterile powder reconstitution. The compound may be administered in the form of injection for more than once daily administration, or intravenous infusion/drip or suitable depot preparation.

EXAMPLE 84 Preparation Suitable for Parenteral Administration has the Following Composition

[0284] Active ingredient of formula I as given above Polyethylene glycol (400) 0.75 ml Sodium metabisuiphite 0.01% Isotonic saline/WFI q.s.

[0285] Other Formulations.

[0286] For the dermatological application and for the discoloration of teeth, the recommended formulations are lotions, oral rinse and toothpaste containing appropriate amount of the compounds of the general formula I.

[0287] The above examples are presented by way of illustration alone and in no way limit the scope of the invention. 

What is claimed is:
 1. A compound represented by general formula (I), and its pharmaceutically acceptable salts:

wherein R₁ is —R₄—R₅ or —N(R₇) N (R₇)R₉; R₄ is selected from the group consisting of —N(R₇)R₆O—, —N(R₇)R₆N(R₇), —OR₆O, and —OR₆N(R₇)—, where R₆ is alkyl with C₂-C₈ Carbon atoms; R₅ is selected from the group consisting of alkyl, aryl including heteroaryl, —COR₇, —SO₂R₇, —C(S) NHR₇, —C(NH)NHR₇, —COR₁₀,

 where R₇ is selected from the group consisting of H, alkyl and aryl including heteroaryl, provided R₇ may be the same or different for R₁ and R₃ in the same compound; R₂ is selected from the group consisting of F, Cl, Br, I, OR₇, NO₂, alkyl, aryl including heteroaryl, formyl, acyl, C(O)NR₇R₁₀, C(O)OR₇, NR₇R₁₀, N═C(R₇)(R₁₀), SR₇, SO₂NH₂, SO₂ alkyl and SO₂aryl; m is 0, 1 or 2; R₃ is selected from the group consisting of R₇, OR₇, N(R₇) (R₁₀), N═C(R₇)(R₁₀), N(R₇)N(R₇)(R₁₀), N(R₇)N═C(R₇)(R₁₀) and CH(R₇)C(O)R₈ where R₈ is selected from the group consisting of R₇, OR₇ and NR₇R₁₀; R₉ is selected from the group consisting of hydrogen, alkyl, aryl including heteroaryl, C(O)R₁₀, —SO₂R₁₀, C(S)NHR₁₀, C(NH) NH (R₁₀) and C(O) NHR₁₀; R₁₀ is selected for the group consisting of H, alkyl and aryl, including heteroaryl and in each case may be the same or different from substituent R₇, provided R₁₀ may be the same or different for R₁ and R₃ in the same compound; X is selected from group consisting of a halide ion, acetate ion, perchlorate ion, sulfonate ion, oxalate ion, citrate ion, tosylate ion, maleate ion, mesylate ion, carbonate ion, sulfite ion, phosphoric hydrogen ion, phosphonate ion, phosphate ion, BF₄ ⁻ and PF₆ ⁻; with proviso that, (i) when two alkyl groups are present on the same carbon or nitrogen, they may be linked together to form a cyclic structure and (ii) the nitrogen of heteroaryl ring of R₁₀, when present, may be quaternized.
 2. The compound as claimed in claim 1, wherein —C(O)R₁ group is at position 3 or
 4. 3. The compound as claimed in claim 2, wherein the position for —C(O)R₁ group is at position
 3. 4. The compound as claimed in claim 1, wherein m is 0 or
 1. 5. The compound as claimed in claim 2, wherein m is 0 or
 1. 6. The compound as claimed in claim 3, wherein m is 0 or
 1. 7. The compound as claimed in claim 1, wherein m is
 0. 8. The compound as claimed in claim 2, wherein m is
 0. 9. The compound as claimed in claim 3, wherein m is
 0. 10. The compound as claimed in claim 1, wherein X is a halide ion.
 11. The compound as claimed in claim 1, which is selected from the group consisting of the following compounds: (a) N,N′-bis[3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl)-3-pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (b) 1-(2-ethoxy-2-oxoethyl)-3-(2-(2-pyridyl)hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (c) 1-(2-ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethylamino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (d) N,N′-bis[3-carbonyl-1-(2-phenyl-2-oxoethyl)pyridinium]hydrazine dibromide and pharmaceutically acceptable salts thereof, (e) 1-(2-phenyl-2-oxoethyl)-3-(hydrazinocarbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof, (f) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (g) N,N′-bis[3-carbonyl-1-(2-(2′,4′-dichlorophenyl)-2-oxoethyl) pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (h) 1-(2-phenyl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (i) 1-(2-ethoxy-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (j) 1-(2-phenyl-2-oxoethyl)-3-(phenylsulfonylhydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (k) 1-(2-phenyl-2-oxoethyl)-2-chloro-3-(phenylsulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (l) 1-(2-thien-2′-yl-2-oxoethyl)-4-(2-(benzoyloxy) ethyl aminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (m) 1-(2-(2,′4′-dichlorophenyl)-2-oxoethyl)-3-(2-(benzoyloxy) ethylaminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (n) 1-(2-phenyl-2-oxoethyl)-3-(2-(acetoxy) ethyloxy) carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof and (o) 1-(2-ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethyloxy carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof.
 12. The compound as claimed in claim 1, which is selected from the group consisting of the following compounds: (p) 1-(2-phenylamino-2-oxoethyl)-4-(phenylsulfonyl hydrazino carbonyl)pyridinium chloride and pharmaceutically acceptable salts thereof, (q) 1-(2-(2,′4′-dichlorophenyl)-2-oxoethyl)-3-(2(methoxy) ethyloxycarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (r) 1-(2-phenylamino-2-oxoethyl)-3-((benzoyloxy) ethylaminocarbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (s) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenylaminocarbonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (t) 1-(2-phenyl-2-oxoethyl)-3-(2-(acetoxy) ethylaminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (u) 1-(2-phenylamino-2-oxoethyl)-3-(phenyl sulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (v) 1-(2-phenylamino-2-oxoethyl)-3-((4-methylphenyl)sulfonyl hydrazinocarbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (w) 1-(2-phenyl-2-oxoethyl)-3-(2-(benzoyloxy)ethyloxy carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (x) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenylcarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (y) 1-(2-ethoxy-2-oxoethyl)-3-((phenylmethyl)sulfonyl hydrazino carbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof and (z) 1-(2-phenyl-2-oxoethyl)-3-((phenylmethyl)sulfonyl hydrazino carbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof.
 13. The compound as claimed in claim 1, which is selected from the group consisting of the following compounds: (aa) N,N′-bis[3-carbonyl-1-(2-furan-2′-yl-2-oxoethyl) pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (ab) N,N′bis [3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ac) N,N′-bis-[3-carbonyl-1-(2-cyclopropylamino-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ad) 1-(2′,4′-dichlorophenyl-2-oxoethyl)-3-(2-methoxyethyl aminocarbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof, (ae) 1-(2-thien-2′-yl-2-oxoethyl)-3-((2-methoxy ethyl) amino carbonyl)-5-bromo pyridinium chloride and pharmaceutically acceptable salts thereof, (af) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (ag) 1-(2-thien-2′yl-2-oxoethyl)-3-(2-(2-chloro-3-pyridoylhydrazinocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (ah) 1-(2-cyclopropylamino-2-oxoethyl)-3-(2-methoxyethylaminocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (ai) 1-(2-isopropylamino-2-oxoethyl)-3-(2-methylsulfonylhydrazinocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (aj) 1-(2-phenylamino-2-oxo ethyl)-3-({2-(1-oxo-3-cyclohexyl)-propyl}-hydrazinocarbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof, (ak) 1-(2-thien-2′-yl-2-oxoethyl)-3-[2-(benzoyloxy)ethylamino carbonyl]-pyridinium bromide and pharmaceutically acceptable salts thereof, (al) 1-(4-ethoxy-2,4-dioxobutyl)-3-(2-(benzoxyloxy)ethylamino carbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, and (am) 1-(2-thien-2′-yl-2-oxoethyl)-3-[1-oxo-1-(2-methoxy carbonyl) pyridyl] hydrazino pyridinium chloride and pharmaceutically acceptable salts thereof.
 14. The compound as claimed in claim 1, which is selected from the group consisting of the following compounds: (an) 1-[1-(2-thien-2′-yl-2-oxoethyl)-5-aminocarbonyl-3-carbonyl pyridinium]-2-[1-(2-thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ao) 1-(2-thien-2′-yl-2-oxoethyl)-3-(trifluoromethanesulfonyl hydrazino carbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof, (ap) 1-[1-(2-thien-2′-yl-2-oxoethyl)-6-methyl-3-carbonyl pyridinium]-2-[1-(2-thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (aq) N,N′-bis[3-carbonyl-1-(2-(5-methyl-thien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ar) N,N′-bis[3-carbonyl-1-(2-(5-chloro-thien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (as) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl)-6-methyl pyridinium bromide and pharmaceutically acceptable salts thereof, (at) N,N′-bis[3-carbonyl-1-(2-(4-nitro-thien-2-yl)-2-oxoethyl)pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (au) 1-(2-phenylamino-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (av) 1-(2-(4-nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (aw) 1-(2-(5-nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (ax) 1-(2-(5-chloro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (ay) 1-(2-thien-2′-yl-2-oxoethyl)-3-(ethoxycarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (az) 1-(2-thien-2′-yl-2-oxoethyl)-3-(isopropylsulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (ba) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl)-5-bromo pyridinium bromide and pharmaceutically acceptable salts thereof, (bb) 1-(2-(2-ethoxy carbonyl pyrrolidin-1-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bc) 1-(2-(5-methyl-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bd) 1-(2-(4-carbethoxy-thiazolidin-3-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (be) 1-(2-(4-benzyl piperidin-1-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bf) N,N′-bis[3-carbonyl-1-(2-(2-ethoxycarbonyl pyrrolidin-1-yl)-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically (bg) 1-(2-phenylamino-2-oxoethyl)-4-[2-(benzoyloxy) ethylamino carbonyl] pyridinium chloride and pharmaceutically acceptable salts thereof, (bh) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bi) 1-(2-thien-2′-yl-2-oxoethyl)-3-(p-methoxy phenyl sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bj) 1-(2-ethoxy-2-oxoethyl)-3-(phenyl aminocarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bk) 1-(2-ethoxy-2-oxoethyl)-3-(p-toluene sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bl) 1-(2-phenyl-2-oxoethyl)-3-(phenylamino carbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bm) 1-(2-phenylamino-2-oxoethyl)-3-(benzyl sulfonyl hydrazino carbonyl) pyridiniumchloride and pharmaceutically acceptable salts thereof, (bn) 1-(2-phenyl-2-oxoethyl)-4-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bo) 1-(2-phenyl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bp) 1-(2-ethoxy-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide and pharmaceutically acceptable salts thereof, (bq) 1-(2-ethoxy-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (br) 1-(2-phenyl-2-oxoethyl)-3-(p-methoxyphenyl sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bs) 1-(2-phenyl-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide and pharmaceutically acceptable salts thereof, and (bt) 1-(2-ethoxy-2-oxoethyl)-4-(p-methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof.
 15. A process for the preparation of the compound represented by general formula (I) as claimed in claim 1, which comprises preparing a substituted pyridine, followed by quaternizing the substituted pyridine, with a quaternizing reagent in an alcoholic and/or high boiling solvent under reflux for 6-48 hrs. to give the desired compound
 16. The compound of general formula I as defined in clain 1, for use as a medicament in the treatment of diabetic complications and aging-related diseases.
 17. The compound of general formula I as defined in claim 1, for use as a medicament in the treatment of vascular and neurovascular complications.
 18. The compound of general formula (I), as defined in claim 1, for use as a medicament in the treatment of kidney disease, nerve damage, retinopathy, atherosclerosis, microangiopathy, endothelial dysfunctions, dermatological conditions and discoloration of teeth.
 19. The compound of general formula (I), as defined in claim 1, for use as a medicament in the treatment of inflammatory discorders, immunological discorders, oxidative stress and other organ dysfunctions including vascular dysfunctions.
 20. A pharmaceutical composition comprising a pharmaceutically effective amount of one or more compounds represented by general formula (I), as defined in claim 1 or pharmaceutically acceptable salt(s) thereof in admixture with a pharmaceutically acceptable carrier, diluent, solvent or excepient.
 21. The pharmaceutical composition as claimed in claim 20, in the form of an oral formulation.
 22. The pharmaceutical composition as claimed in claim 20, wherein said acceptable carier, diluent, solvent or excepient is selected from group consisting of starch, lactose, polyvinyl pyrolidone (K-30), talc and magnesium stearate.
 23. The pharmaceutical composition as claimed in claim 20 in the form of a parenteral formulation.
 24. A method for the preparation of a parenteral formulation as claimed in claim 23, which comprises dissolving one or more compounds represented by general formula (I), as defined in claim 1, in polyethylene glycol 400 and diluting the solution so obtained, with an isotonic solution or water to a desired concentration.
 25. Pharmaceutical composition as claimed in claim 20, in the form of a lotion, oral rinse and toothpaste.
 26. The pharmaceutical composition as claimed claim 20 wherein said compound is selected from the group consisting of: (a) N,N′-bis[3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl)-3-pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (b) 1-(2-ethoxy-2-oxoethyl)-3-(2-(2-pyridyl)hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (c) 1-(2-ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethylamino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (d) N,N′-bis[3-carbonyl-1-(2-phenyl-2-oxoethyl)pyridinium]hydrazine dibromide and pharmaceutically acceptable salts thereof, (e) 1-(2-phenyl-2-oxoethyl)-3-(hydrazinocarbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof, (f) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (g) N,N-bis[3-carbonyl-1-(2-(2′,4′-dichlorophenyl)-2-oxoethyl) pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (h) 1-(2-phenyl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (i) 1-(2-ethoxy-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (j) 1-(2-phenyl-2-oxoethyl)-3-(phenylsulfonylhydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (k) 1-(2-phenyl-2-oxoethyl)-2-chloro-3-(phenylsulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (l) 1-(2-thien-2′-yl-2-oxoethyl)-4-(2-(benzoyloxy) ethyl aminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (m) 1-(2-(2,′4′-dichlorophenyl)-2-oxoethyl)-3-(2-(benzoyloxy) ethylaminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (n) 1-(2-phenyl-2-oxoethyl)-3-(2-(acetoxy) ethyloxy) carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof and (o) 1-(2-ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethyloxy carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof.
 27. The pharmaceutical composition as claimed claim 20 wherein said compound is selected from the group consisting of: (p) 1-(2-phenylamino-2-oxoethyl)-4-(phenylsulfonyl hydrazino carbonyl)pyridinium chloride and pharmaceutically acceptable salts thereof, (q) 1-(2-(2,′4′-dichlorophenyl)-2-oxoethyl)-3-(2(methoxy) ethyloxycarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (r) 1-(2-phenylamino-2-oxoethyl)-3-((benzoyloxy) ethylaminocarbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (s) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenylaminocarbonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (t) 1-(2-phenyl-2-oxoethyl)-3-(2-(acetoxy) ethylaminocarbonyl) pyridinium bromide or other pharmaceutically acceptable salts thereof, (u) 1-(2-phenylamino-2-oxoethyl)-3-(phenyl sulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (v) 1-(2-phenylamino-2-oxoethyl)-3-((4-methylphenyl)sulfonyl hydrazinocarbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (w) 1-(2-phenyl-2-oxoethyl)-3-(2-(benzoyloxy)ethyloxy carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (x) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenylcarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (y) 1-(2-ethoxy-2-oxoethyl)-3-((phenylmethyl)sulfonyl hydrazino carbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof and (z) 1-(2-phenyl-2-oxoethyl)-3-((phenylmethyl)sulfonyl hydrazino carbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof.
 28. The pharmaceutical composition as claimed claim 20 wherein said compound is selected from the group consisting of: (aa) N,N′-bis[3-carbonyl-1-(2-furan-2′-yl-2-oxoethyl) pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (ab) N,N′-bis[3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ac) N,N′-bis-[3-carbonyl-1-(2-cyclopropylamino-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ad) 1-(2′,4′-dichlorophenyl-2-oxoethyl)-3-(2-methoxyethyl aminocarbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof, (ae) 1-(2-thien-2′-yl-2-oxoethyl)-3-((2-methoxy ethyl) amino carbonyl)-5-bromo pyridinium chloride and pharmaceutically acceptable salts thereof, (af) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (ag) 1-(2-thien-2′yl-2-oxoethyl)-3-(2-(2-chloro-3-pyridoylhydrazinocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (ah) 1-(2-cyclopropylamino-2-oxoethyl)-3-(2-methoxyethylaminocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (ai) 1-(2-isopropylamino-2-oxoethyl)-3-(2-methylsulfonylhydrazinocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (aj) 1-(2-phenylamino-2-oxo ethyl)-3-({2-(1-oxo-3-cyclohexyl)-propyl}-hydrazino-carbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof, (ak) 1-(2-thien-2′-yl-2-oxoethyl)-3-[2-(benzoyloxy)ethylamino carbonyl]-pyridinium bromide and pharmaceutically acceptable salts thereof, (al) 1-(4-ethoxy-2,4-dioxobutyl)-3-(2-(benzoxyloxy)ethylamino carbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, and (am)1-(2-thien-2′-yl-2-oxoethyl)-3-[1-oxo-1-(2-methoxy carbonyl) pyridyl] hydrazino pyridinium chloride and pharmaceutically acceptable salts thereof.
 29. The pharmaceutical composition as claimed claim 20 wherein said compound is selected from the group consisting of: (an) 1-[1-(2-thien-2′-yl-2-oxoethyl)-5-aminocarbonyl-3-carbonyl pyridinium]-2-[1-(2-thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof. (ao) 1-(2-thien-2′-yl-2-oxoethyl)-3-(trifluoromethanesulfonyl hydrazino carbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof. (ap) 1-[1-(2-thien-2′-yl-2-oxoethyl)-6-methyl-3-carbonyl pyridinium]-2-[1-(2-thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof. (aq) N,N′-bis[3-carbonyl-1-(2-(5-methyl-thien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof. (ar) N,N′-bis[3-carbonyl-1-(2-(5-chloro-thien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof. (as) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl)-6-methyl pyridinium bromide and pharmaceutically acceptable salts thereof, (at) N,N′-bis[3-carbonyl-1-(2-(4-nitro-thien-2-yl)-2-oxoethyl)pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (au) 1-(2-phenylamino-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (av) 1-(2-(4-nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof. (aw) 1-(2-(5-nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and other pharmaceutically acceptable salts thereof and pharmaceutically acceptable salts thereof, (ax) 1-(2-(5-chloro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (ay) 1-(2-thien-2′-yl-2-oxoethyl)-3-(ethoxycarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (az) 1-(2-thien-2′-yl-2-oxoethyl)-3-(isopropylsulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (ba) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) -5-bromo pyridinium bromide and pharmaceutically acceptable salts thereof, (bb) 1-(2-(2-ethoxy carbonyl pyrrolidin-1-yl)-2-oxoethyl) -3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bc) 1-(2-(5-methyl-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bd) 1-(2-(4-carbethoxy-thiazolidin-3-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (be) 1-(2-(4-benzyl piperidin-1-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bf) N,N′-bis[3-carbonyl-1-(2-(2-ethoxycarbonyl pyrrolidin-1-yl) -2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically (bg) 1-(2-phenylamino-2-oxoethyl)-4-[2-(benzoyloxy) ethylamino carbonyl] pyridinium chloride and pharmaceutically acceptable salts thereof, (bh) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bi) 1-(2-thien-2′-yl-2-oxoethyl)-3-(p-methoxy phenyl sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bj) 1-(2-ethoxy-2-oxoethyl)-3-(phenyl aminocarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bk) 1-(2-ethoxy-2-oxoethyl)-3-(p-toluene sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bl) 1-(2-phenyl-2-oxoethyl)-3-(phenylamino carbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bm) 1-(2-phenylamino-2-oxoethyl)-3-(benzyl sulfonyl hydrazino carbonyl) pyridiniumchloride and pharmaceutically acceptable salts thereof, (bn) 1-(2-phenyl-2-oxoethyl)-4-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bo) 1-(2-phenyl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bp) 1-(2-ethoxy-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide and pharmaceutically acceptable salts thereof, (bq) 1-(2-ethoxy-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (br) 1-(2-phenyl-2-oxoethyl)-3-(p-methoxyphenyl sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bs) 1-(2-phenyl-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide and pharmaceutically acceptable salts thereof, and (bt) 1-(2-ethoxy-2-oxoethyl)-4-(p-methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof.
 30. A method for treating a diabetic patient by breaking a preformed AGE, within said patient, which comprises, administering an effective amount of a compound represented by general formula (I) as claimed in claim 1, either singly, or in combination with other drugs for antidiabetic therapy.
 31. A method of preventing or treating diseases caused by diabetes and aging related complications including vascular and neurovascular complications, which comprises, administering to a patient in need thereof, an effective amount of a compound represented by general formula (I), as claimed in claim 1, either singly or in combination with a pharmaceutically acceptable carrier, diluent or excepient.
 32. The method as claimed in claim 31, wherein the disease prevented or treated is a nephrological disorder, neurological disorder, atherosclerosis, retinal disorder, dermatological disorder, non-enzymatic browing of oral cavity, endothelial or other organ dysfunction and growth impairment.
 33. The method as claimed in claim 31, wherein the disease prevented or treated is an inflammatory disorder, immunological disorder, or oxidative stress.
 34. The method as claimed in claim 30, wherein said compound is selected from the group consisting of: (a) N,N′-bis[3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl)-3-pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (b) 1-(2-ethoxy-2-oxoethyl)-3-(2-(2-pyridyl)hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (c) 1-(2-ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethylamino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (d) N,N′-bis[3-carbonyl-1-(2-phenyl-2-oxoethyl)pyridinium]hydrazine dibromide and pharmaceutically acceptable salts thereof, (e) 1-(2-phenyl-2-oxoethyl)-3-(hydrazinocarbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof, (f) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (g) N,N′-bis[3-carbonyl-1-(2-(2′,4′-dichlorophenyl)-2-oxoethyl) pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (h) 1-(2-phenyl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (i) 1-(2-ethoxy-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (j) 1-(2-phenyl-2-oxoethyl)-3-(phenylsulfonylhydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (k) 1-(2-phenyl-2-oxoethyl)-2-chloro-3-(phenylsulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (l) 1-(2-thien-2′-yl-2-oxoethyl)-4-(2-(benzoyloxy) ethyl aminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof. (m) 1-(2-(2,′4′-dichlorophenyl)-2-oxoethyl)-3-(2-(benzoyloxy) ethylaminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (n) 1-(2-phenyl-2-oxoethyl)-3-(2-(acetoxy) ethyloxy) carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, and (o) 1-(2-ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethyloxy carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof.
 35. The method as claimed in claim 30, wherein said compound is selected from the group consisting of: (p) 1-(2-phenylamino-2-oxoethyl)-4-(phenylsulfonyl hydrazino carbonyl)pyridinium chloride and pharmaceutically acceptable salts thereof, (q) 1-(2-(2,′4′-dichlorophenyl)-2-oxoethyl)-3-(2(methoxy) ethyloxycarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (r) 1-(2-phenylamino-2-oxoethyl)-3-((benzoyloxy) ethylaminocarbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (s) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenylaminocarbonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (t) 1-(2-phenyl-2-oxoethyl)-3-(2-(acetoxy) ethylaminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (u) 1-(2-phenylamino-2-oxoethyl)-3-(phenyl sulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (v) 1-(2-phenylamino-2-oxoethyl)-3-((4-methylphenyl)sulfonyl hydrazinocarbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (w) 1-(2-phenyl-2-oxoethyl)-3-(2-(benzoyloxy)ethyloxy carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (x) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenylcarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (y) 1-(2-ethoxy-2-oxoethyl)-3-((phenylmethyl)sulfonyl hydrazino carbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof and (z) 1-(2-phenyl-2-oxoethyl)-3-((phenylmethyl)sulfonyl hydrazino carbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof.
 36. The method as claimed in claim 30, wherein said compound is selected from the group consisting of: (aa) N,N′-bis[3-carbonyl-1-(2-furan-2′-yl-2-oxoethyl) pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (ab) N,N′-bis[3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ac) N,N′-bis-[3-carbonyl-1-(2-cyclopropylamino-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ad) 1-(2′,4′-dichlorophenyl-2-oxoethyl)-3-(2-methoxyethyl aminocarbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof, (ae) 1-(2-thien-2′-yl-2-oxoethyl)-3-((2-methoxy ethyl) amino carbonyl)-5-bromo pyridinium chloride and pharmaceutically acceptable salts thereof, (af) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (ag) 1-(2-thien-2′yl-2-oxoethyl)-3-(2-(2-chloro-3-pyridoylhydrazinocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (ah) 1-(2-cyclopropylamino-2-oxoethyl)-3-(2-methoxyethylaminocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (ai) 1-(2-isopropylamino-2-oxoethyl)-3-(2-methylsulfonylhydrazinocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (aj) 1-(2-phenylamino-2-oxo ethyl)-3-({2-(1-oxo-3-cyclohexyl)-propyl}-hydrazino-carbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof, (ak) 1-(2-thien-2′-yl-2-oxoethyl)-3-[2-(benzoyloxy)ethylamino carbonyl]-pyridinium bromide and pharmaceutically acceptable salts thereof, (al) 1-(4-ethoxy-2,4-dioxobutyl)-3-(2-(benzoxyloxy)ethylamino carbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, and (am) 1-(2-thien-2′-yl-2-oxoethyl)-3-[1-oxo-1-(2-methoxy carbonyl) pyridyl] hydrazino pyridinium chloride and pharmaceutically acceptable salts thereof.
 37. The method as claimed in claim 30, wherein said compounds selected from the group consistaing of: (an) 1-[1-(2-thien-2′-yl-2-oxoethyl)-5-aminocarbonyl-3-carbonyl pyridinium]-2-[1-(2-thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ao) 1-(2-thien-²′-yl-2-oxoethyl)-3-(trifluoromethanesulfonyl hydrazino carbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof. (ap) 1-[1-(2-thien-2′-yl-2-oxoethyl)-6-methyl-3-carbonyl pyridinium]-2-[1-(2-thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof (aq) N,N′-bis[3-carbonyl-1-(2-(5-methyl-thien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ar) N,N′-bis[3-carbonyl-1-(2-(5-chloro-thien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (as) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl)-6-methyl pyridinium bromide and pharmaceutically acceptable salts thereof, (at) N,N′-bis[3-carbonyl-1-(2-(4-nitro-thien-2-yl)-2-oxoethyl)pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (au) 1-(2-phenylamino-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium chloride or other pharmaceutically acceptable salts thereof, (av) 1-(2-(4-nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (aw) 1-(2-(5-nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (ax) 1-(2-(5-chloro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (ay) 1-(2-thien-2′-yl-2-oxoethyl)-3-(ethoxycarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (az) 1-(2-thien-2′-yl-2-oxoethyl)-3-(isopropylsulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (ba) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl)-5-bromo pyridinium bromide and pharmaceutically acceptable salts thereof, (bb) 1-(2-(2-ethoxy carbonyl pyrrolidin-1-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bc) 1-(2-(5-methyl-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bd) 1-(2-(4-carbethoxy-thiazoldin-3-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (be) 1-(2-(4-benzyl piperidin-1-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bf) N,N′-bis[3-carbonyl-1-(2-(2-ethoxycarbonyl pyrrolidin-1-yl)-2-oxoethyl) pyridinium] hydrazine dichloride or other pharmaceutically (bg) 1-(2-phenylamino-2-oxoethyl)-4-[2-(benzoyloxy) ethylamino carbonyl] pyridinium chloride and pharmaceutically acceptable salts thereof, (bh) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bi) 1-(2-thien-2′-yl-2-oxoethyl)-3-(p-methoxy phenyl sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bj) 1-(2-ethoxy-2-oxoethyl)-3-(phenyl aminocarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bk) 1-(2-ethoxy-2-oxoethyl)-3-(p-toluene sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bl) 1-(2-phenyl-2-oxoethyl)-3-(phenylamino carbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bm) 1-(2-phenylamino-2-oxoethyl)-3-(benzyl sulfonyl hydrazino carbonyl) pyridiniumchloride and pharmaceutically acceptable salts thereof, (bn) 1-(2-phenyl-2-oxoethyl)-4-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bo) 1-(2-phenyl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bp) 1-(2-ethoxy-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide and pharmaceutically acceptable salts thereof, (bq) 1-(2-ethoxy-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (br) 1-(2-phenyl-2-oxoethyl)-3-(p-methoxyphenyl sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bs) 1-(2-phenyl-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide and pharmaceutically acceptable salts thereof, and (bt) 1-(2-ethoxy-2-oxoethyl)-4-(p-methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof.
 38. The method as claimed in claim 31 wherein said compound is selected from the group consisting of: (a) N,N′-bis[3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl)-3-pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (b) 1-(2-ethoxy-2-oxoethyl)-3-(2-(2-pyridyl)hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (c) 1-(2-ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethylamino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (d) N,N′-bis[3-carbonyl-1-(2-phenyl-2-oxoethyl)pyridinium]hydrazine dibromide and pharmaceutically acceptable salts thereof, (e) 1-(2-phenyl-2-oxoethyl)-3-(hydrazinocarbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof, (f) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (g) N,N′-bis[3-carbonyl-1-(2-(2′,4′-dichlorophenyl)-2-oxoethyl) pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (h) 1-(2-phenyl-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (i) 1-(2-ethoxy-2-oxoethyl)-3-(methanesulfonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (j) 1-(2-phenyl-2-oxoethyl)-3-(phenylsulfonylhydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (k) 1-(2-phenyl-2-oxoethyl)-2-chloro-3-(phenylsulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (l) 1-(2-thien-2′-yl-2-oxoethyl)-4-(2-(benzoyloxy) ethyl aminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (m) 1(2-(2,′4′-dichlorophenyl)-2-oxoethyl)-3-(2-(benzoyloxy) ethylaminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (n) 1-(2-phenyl-2-oxoethyl)-3-(2-(acetoxy) ethyloxy) carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof and (o) 1-(2-ethoxy-2-oxoethyl)-3-(2-(benzoyloxy) ethyloxy carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof.
 39. The method as claimed in claim 31, wherein said compound is selected from the group consisting of: (p) 1-(2-phenylamino-2-oxoethyl)-4-(phenylsulfonyl hydrazino carbonyl)pyridinium chloride and pharmaceutically acceptable salts thereof, (q) 1-(2-(2,′4′-dichlorophenyl)-2-oxoethyl)-3-(2(methoxy) ethyloxycarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (r) 1-(2-phenylamino-2-oxoethyl)-3-((benzoyloxy) ethylaminocarbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (s) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenylaminocarbonyl hydrazinocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (t) 1-(2-phenyl-2-oxoethyl)-3-(2-(acetoxy) ethylaminocarbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (u) 1-(2-phenylamino-2-oxoethyl)-3-(phenyl sulfonyl hydrazino carbonyl) pyridiniun chloride and pharmaceutically acceptable salts thereof, (v) 1-(2-phenylamino-2-oxoethyl)-3-((4-methylphenyl)sulfonyl hydrazinocarbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (w) 1-(2-phenyl-2-oxoethyl)-3-(2-(benzoyloxy)ethyloxy carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (x) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenylcarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (y) 1-(2-ethoxy-2-oxoethyl)-3-((phenylmethyl)sulfonyl hydrazino carbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof and (z)1-(2-phenyl-2-oxoethyl)-3-((phenylmethyl)sulfonyl hydrazino carbonyl)pyridinium bromide and pharmaceutically acceptable salts thereof.
 40. The method as claimed in claim 31, wherein said compound is selected from the group consisting of: (aa) N,N′-bis[3-carbonyl-1-(2-furan-2′-yl-2-oxoethyl) pyridinium] hydrazine dibromide and pharmaceutically acceptable salts thereof, (ab) N,N′-bis[3-carbonyl-1-(2-thien-2′-yl-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ac) N,N′-bis-[3-carbonyl-1-(2-cyclopropylamino-2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically acceptable salts thereof, (ad) 1-(2′,4′-dichlorophenyl-2-oxoethyl)-3-(2-methoxyethyl aminocarbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof, (ae) 1-(2-thien-2′-yl-2-oxoethyl)-3-((2-methoxy ethyl) amino carbonyl)-5-bromo pyridinium chloride and pharmaceutically acceptable salts thereof, (af) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (ag) 1-(2-thien-2′yl-2-oxoethyl)-3-(2-(2-chloro-3-pyridoylhydrazinocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (ah) 1-(2-cyclopropylamino-2-oxoethyl)-3-(2-methoxyethylaminocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (ai) 1-(2-isopropylamino-2-oxoethyl)-3-(2-methylsulfonylhydrazinocarbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, (aj) 1-(2-phenylamino-2-oxo ethyl)-3-({2-(1-oxo-3-cyclohexyl)-propyl}-hydrazino-carbonyl)-pyridinium bromide and pharmaceutically acceptable salts thereof, (ak) 1-(2-thien-2′-yl-2-oxoethyl)-3-[2-(benzoyloxy)ethylamino carbonyl]-pyridinium bromide and pharmaceutically acceptable salts thereof, (al) 1-(4-ethoxy-2,4-dioxobutyl)-3-(2-(benzoxyloxy)ethylamino carbonyl)-pyridinium chloride and pharmaceutically acceptable salts thereof, and (am) 1-(2-thien-2′-yl-2-oxoethyl)-3-[1-oxo-1-(2-methoxy carbonyl) pyridyl] hydrazino pyridinium chloride and pharmaceutically acceptable salts thereof.
 41. The method as claimed in claim 31, wherein said compound s selected from the group consistaing of: (an) 1-[1-(2-thien-2′-yl-2-oxoethyl5-aminocarbonyl-3-carbonyl pyridinium]-2-[1-(2-thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium] hydrazine dichlorid chloride and pharmaceutically acceptable salts thereof, (ao) 1-(2-thien-2′-yl-2-oxoethyl)-3-(trifluoromethanesulfonyl hydrazino carbonyl)- pyridinium bromide chloride and pharmaceutically acceptable salts thereof, (ap) 1-[1-(2-thien-2′-yl-2-oxoethyl)-6-methyl-3-carbonyl pyridinium]-2-[1-(2-thien-2′-yl-2-oxoethyl)-3-carbonyl pyridinium ] hydrazine dichloride chloride and pharmaceutically acceptable salts thereof, (aq) N,N′-bis[3-carbonyl-1-(2-(5-methyl-thien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride chloride and pharmaceutically acceptable salts thereof, (ar) N,N′-bis[3-carbonyl-1-(2-(5-chloro-thien-2-yl)-2-oxoethyl) pyridinium] hydrazine dichloride chloride and pharmaceutically acceptable salts thereof, (as) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl)-6-methyl pyridinium bromide chloride and pharmaceutically acceptable salts thereof, (at) N,N′-bis[3-carbonyl-1-(2-(4-nitro-thien-2-yl)-2-oxoethyl)pyridinium] hydrazine dichloride chloride and pharmaceutically acceptable salts thereof, (au) 1-(2-phenylamino-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium chloride chloride and pharmaceutically acceptable salts thereof, (av) 1-(2-(4-nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide chloride and pharmaceutically acceptable salts thereof, (aw) 1-(2-(5-nitro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (ax) 1-(2-(5-chloro-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (ay) 1-(2-thien-2′-yl-2-oxoethyl)-3-(ethoxycarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (az) 1-(2-thien-2′-yl-2-oxoethyl)-3-(isopropylsulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (ba) 1-(2-thien-2′-yl-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) -5-bromo pyridinium bromide and pharmaceutically acceptable salts thereof, (bb) 1-(2-(2-ethoxy carbonyl pyrrolidin-1-yl)-2-oxoethyl) -3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bc) 1-(2-(5-methyl-thien-2-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bd) 1-(2-(4-carbethoxy-thiazolidin-3-yl)-2-oxoethyl) -3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (be) 1-(2-(4-benzyl piperidin-1-yl)-2-oxoethyl)-3-(methanesulfonyl hydrazino carbonyl) pyridinium chloride and pharmaceutically acceptable salts thereof, (bf) N,N′-bis[3-carbonyl-1-(2-(2-ethoxycarbonyl pyrrolidin-1-yl) -2-oxoethyl) pyridinium] hydrazine dichloride and pharmaceutically (bg) 1-(2-phenylamino-2-oxoethyl)-4-[2-(benzoyloxy) ethylamino carbonyl] pyridinium chloride and pharmaceutically acceptable salts thereof, (bh) 1-(2-thien-2′-yl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bi) 1-(2-thien-2′-yl-2-oxoethyl)-3-(p-methoxy phenyl sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bj) 1-(2-ethoxy-2-oxoethyl)-3-(phenyl aminocarbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bk) 1-(2-ethoxy-2-oxoethyl)-3-(p-toluene sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bl) 1-(2-phenyl-2-oxoethyl)-3-(phenylamino carbonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bm) 1-(2-phenylamino-2-oxoethyl)-3-(benzyl sulfonyl hydrazino carbonyl) pyridiniumchloride and pharmaceutically acceptable salts thereof, (bn) 1-(2-phenyl-2-oxoethyl)-4-(methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bo) 1-(2-phenyl-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bp) 1-(2-ethoxy-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide and pharmaceutically acceptable salts thereof, (bq) 1-(2-ethoxy-2-oxoethyl)-3-(phenyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (br) 1-(2-phenyl-2-oxoethyl)-3-(p-methoxyphenyl sulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof, (bs) 1-(2-phenyl-2-oxoethyl)-4-[2-(benzoyloxy) ethyl amino carbonyl] pyridinium bromide and pharmaceutically acceptable salts thereof, and (bt) 1-(2-ethoxy-2-oxoethyl)-4-(p-methanesulfonyl hydrazino carbonyl) pyridinium bromide and pharmaceutically acceptable salts thereof. 